Revert "configure: Colorize output"

The colors are not based on the semantics of the message but rather
on the message itself. This means that the default human-perceived
semantics (red = bad, green = good) don't really apply and spotting a
color does not mean anythting.

This is amplified by the sheer amount of output which configure produces
and the fact that some of the messages have negative semantics or
additional output.

In case of any problem the user will have to go through everything
anyways as spotting a red or yellow line has 0 information value.

Here are a few examples:

1) some 'no' messages are not a problem:

  checking minix/config.h presence... no

2) some 'no' messages are actually positive:

  checking for special C compiler options needed for large files... no

3) in some cases a 'yes' would mean that something is broken or needs
   workaround

  checking whether stat file-mode macros are broken... no
  checking whether wint_t is too small... no
  checking whether stdint.h predates C++11... no
  checking whether the inttypes.h PRIxNN macros are broken... no
  checking whether clang gives bogus warnings for -Wdouble-promotion... no
  checking whether gettimeofday clobbers localtime buffer... no

4) due to string match based colors extra text makes messages yellow

  checking for a traditional french locale... none
  checking for working nanosleep... no (mishandles large arguments)
  checking for library containing gethostbyname... none required
  checking whether mbrtowc handles incomplete characters... (cached) guessing yes

5) in some cases the yes/no is very context dependant

  checking whether pthread_rwlock_rdlock prefers a writer to a reader... no
  checking whether this build is done by a static analysis tool... no

6) detected paths to binaries and libs are yellow despite being present

  checking for objdump... objdump
  checking for atomic ops implementation... gcc

As of the reasons above I don't think the colorization of the configure
output helps users or developers to debug the build process and
thus is not worth the extra code or output clutter.

This reverts commit c98174ce08.

ACKed-by: Michal Prívozník <mprivozn@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>

m4/virt-colours.m4

@@ -1,62 +0,0 @@
-dnl Colourful configure
-dnl
-dnl Copyright (C) 2015 Nobuyoshi Nakada
-dnl
-dnl This library is free software; you can redistribute it and/or
-dnl modify it under the terms of the GNU Lesser General Public
-dnl License as published by the Free Software Foundation; either
-dnl version 2.1 of the License, or (at your option) any later version.
-dnl
-dnl This library is distributed in the hope that it will be useful,
-dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
-dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-dnl Lesser General Public License for more details.
-dnl
-dnl You should have received a copy of the GNU Lesser General Public
-dnl License along with this library.  If not, see
-dnl <http://www.gnu.org/licenses/>.
-
-AC_DEFUN([_COLORIZE_RESULT_PREPARE], [
-    msg_checking= msg_result_yes= msg_result_no= msg_result_other= msg_reset=
-    AS_IF([test -t 1], [
-	msg_begin="`tput smso 2>/dev/null`"
-	AS_CASE(["$msg_begin"], ['@<:@'*m],
-	    [msg_begin="`echo "$msg_begin" | sed ['s/[0-9]*m$//']`"
-	    msg_checking="${msg_begin}33m"
-	    AS_IF([test ${TEST_COLORS:+set}], [
-		msg_result_yes=[`expr ":$TEST_COLORS:" : ".*:pass=\([^:]*\):"`]
-		msg_result_no=[`expr ":$TEST_COLORS:" : ".*:fail=\([^:]*\):"`]
-		msg_result_other=[`expr ":$TEST_COLORS:" : ".*:skip=\([^:]*\):"`]
-	    ])
-	    msg_result_yes="${msg_begin}${msg_result_yes:-32;1}m"
-	    msg_result_no="${msg_begin}${msg_result_no:-31;1}m"
-	    msg_result_other="${msg_begin}${msg_result_other:-33;1}m"
-	    msg_reset="${msg_begin}m"
-	    ])
-	AS_UNSET(msg_begin)
-	])
-    AS_REQUIRE_SHELL_FN([colorize_result],
-	[AS_FUNCTION_DESCRIBE([colorize_result], [MSG], [Colorize result])],
-        [AS_CASE(["$[]1"],
-            [yes], [AS_ECHO(["${msg_result_yes}$[]1${msg_reset}]")],
-            [no], [AS_ECHO(["${msg_result_no}$[]1${msg_reset}]")],
-            [AS_ECHO(["${msg_result_other}$[]1${msg_reset}]")])])
-])
-
-AC_DEFUN([COLORIZE_RESULT], [AC_REQUIRE([_COLORIZE_RESULT_PREPARE])dnl
-    AS_LITERAL_IF([$1],
-	[m4_case([$1],
-		[yes], [AS_ECHO(["${msg_result_yes}$1${msg_reset}"])],
-		[no], [AS_ECHO(["${msg_result_no}$1${msg_reset}"])],
-		[AS_ECHO(["${msg_result_other}$1${msg_reset}"])])],
-	[colorize_result "$1"]) dnl
-])
-
-AC_DEFUN([AC_CHECKING],[dnl
-AC_REQUIRE([_COLORIZE_RESULT_PREPARE])dnl
-AS_MESSAGE([checking ${msg_checking}$1${msg_reset}...])])
-
-AC_DEFUN([AC_MSG_RESULT], [dnl
-{ _AS_ECHO_LOG([result: $1])
-COLORIZE_RESULT([$1]); dnl
-}])