Also we don't need to include module_arch_supported.mk again, if we are
currently substituting the source build with LOCAL_PREBUILT_MODULE_FILE.
Change-Id: I444b0397d74c3153b398a050b762e49418062a86
Prebuilts often support only a single architecture, allow them to
use LOCAL_MODULE_TARGET_ARCH to specify it.
Change-Id: I2514f66f682ef267bbf1a1ab78510faff0a18b64