Fix rtcd build process for Android.mk

Add a dependency so ndk-build will
generate the needed vpx_rtcd.h file.

Change-Id: I92c82e0996943dd0403c9956e1ba60e92e2837a9

build/make/Android.mk

@@ -118,6 +118,10 @@ $(ASM_CNV_PATH)/libvpx/%.asm.s: $(LIBVPX_PATH)/%.asm $(ASM_CNV_OFFSETS_DEPEND)
 	@mkdir -p $(dir $@)
 	@$(CONFIG_DIR)/$(ASM_CONVERSION) <$< > $@
 
+# For building vpx_rtcd.h, which has a rule in libs.mk
+TGT_ISA:=$(word 1, $(subst -, ,$(TOOLCHAIN)))
+target := libs
+$(foreach file, $(LOCAL_SRC_FILES), $(LOCAL_PATH)/$(file)): vpx_rtcd.h
 
 LOCAL_SRC_FILES += vpx_config.c
 
@@ -171,6 +175,7 @@ clean:
 	@$(RM) $(CODEC_SRCS_ASM_ADS2GAS) $(CODEC_SRCS_ASM_NEON_ADS2GAS)
 	@$(RM) $(patsubst %.asm, %.*, $(ASM_CNV_OFFSETS_DEPEND))
 	@$(RM) -r $(ASM_CNV_PATH)
+	@$(RM) $(CLEAN-OBJS)
 
 include $(BUILD_SHARED_LIBRARY)
 

libs.mk

@@ -327,7 +327,7 @@ CLEAN-OBJS += $(BUILD_PFX)vpx_version.h
 # Rule to generate runtime cpu detection files
 #
 $(OBJS-yes:.o=.d): vpx_rtcd.h
-vpx_rtcd.h: $(sort $(filter %rtcd_defs.sh,$(CODEC_SRCS)))
+vpx_rtcd.h: $(SRC_PATH_BARE)/$(sort $(filter %rtcd_defs.sh,$(CODEC_SRCS)))
 	@echo "    [CREATE] $@"
 	$(qexec)$(SRC_PATH_BARE)/build/make/rtcd.sh --arch=$(TGT_ISA) \
           --sym=vpx_rtcd \