[bazel] Set target when assembling .S files (e.g. icu)

Without this, I got the following error on an M1 mac
ld64.lld: error: bazel-out/darwin_arm64-fastbuild-ST-43e14aca42ea/bin/external/icu/libicu.a(generated_icu_mac_dat.o) has architecture x86_64 which is incompatible with target architecture arm64

Bug: skia:12541
Change-Id: I60106a95bcb8dddba45b0a1ada395976ede8fe4e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/562216
Reviewed-by: Jorge Betancourt <jmbetancourt@google.com>
1 file changed