android: mesa: Move the FXT1 compressor/decompressor to util/
After commit a46b73ee in order to build mesa for Android we need to generate $(intermediates)/util/format/u_format_pack.h instead of $(intermediates)/format/u_format_pack.h
Fixes the following building error in Android build:
external/mesa/src/util/format/u_format_fxt1.c:28:10: fatal error: 'util/format/u_format_pack.h' file not found ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated.
Fixes: a46b73ee ("mesa: Move the FXT1 compressor/decompressor to util/")