Android.mk: disable android-libbacktrace to build with Android 14

Android.mk: disable android-libbacktrace to build with Android 14

Android libbacktrace is not available in Android 14

Fixes the following build error:

FAILED: src/util/libmesa_util.a.p/u_debug_stack_android.cpp.o
...
../src/util/u_debug_stack_android.cpp:28:10: fatal error: 'backtrace/Backtrace.h' file not found
         ^~~~~~~~~~~~~~~~~~~~~~~
1 error generated.

Cc: mesa-stable
Reviewed-by: Roman Stratiienko <r.stratiienko@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25963>
(cherry picked from commit 95ad0c750c5891dab3a678f26a74c95edfed87c9)