adb: fix obsolete documentation.

Bug: http://b/110564383 Obsolete adb document, inconsistent with current implementation
Test: N/A
Change-Id: If12ba8546991ee6f2a89ca0ff8036b598742dc11

adb/OVERVIEW.TXT

@@ -103,9 +103,6 @@ II. Protocol details:
            4-byte hex length, followed by a string giving the reason
            for failure.
 
-        3. As a special exception, for 'host:version', a 4-byte
-           hex string corresponding to the server's internal version number
-
     Note that the connection is still alive after an OKAY, which allows the
     client to make other requests. But in certain cases, an OKAY will even
     change the state of the connection.

adb/SERVICES.TXT

@@ -7,10 +7,6 @@ HOST SERVICES:
 host:version
     Ask the ADB server for its internal version number.
 
-    As a special exception, the server will respond with a 4-byte
-    hex string corresponding to its internal version number, without
-    any OKAY or FAIL.
-
 host:kill
     Ask the ADB server to quit immediately. This is used when the
     ADB client detects that an obsolete server is running after an