ANDROID: Fix x86_64 allmodconfig build

The kernel is now being linked with ld.ldd, but this linker will discard
the __memcat_p symbol, even if it is exported, if there are no in-kernel
users. Since the STM driver and test code can be built as a module, they
will fail at modpost time.

While the solution to this bug is still being discussed, keep the
allmodconfig build going by suppressing these options.

Bug: 140224784
Link: https://github.com/ClangBuiltLinux/linux/issues/515


Test: make -j64 ARCH=x86_64 allmodconfig + tweaks
Change-Id: I2942e4b3443180e6bff9820a7c5174c03347ae8a
Signed-off-by: Alistair Delva <adelva@google.com>