adb: Increase the max number of emulator instances to 64

When the ADB server starts, it probes the localhost ports to find
existing emulator instances, starting from 5555 with increments of
2, and stopping after ADB_LOCAL_TRANSPORT_MAX tries, which was
set to 16.

This means that the ADB server could not detect on startup more
than 16 existing emulator instances.

This increases the limit to 64, to match a corresponding change
on the emulator side.

  See https://android-review.googlesource.com/#/c/83553/

Change-Id: I35c69f8017298c3e5797bd396b8d788d44eaa00f

adb/transport_local.c

@@ -48,7 +48,7 @@ static inline void fix_endians(apacket *p)
  * local transport it is connected. The list is used to detect when we're
  * trying to connect twice to a given local transport.
  */
-#define  ADB_LOCAL_TRANSPORT_MAX  16
+#define  ADB_LOCAL_TRANSPORT_MAX  64
 
 ADB_MUTEX_DEFINE( local_transports_lock );