Fix rild running in Nakasi.

The module rild is telephony specific, since Nakasi has no radio
it shouldn't run rild. Make the rild module optional and add a
cleanstep.

Bug: 6463864
Change-Id: Iaf931082ef96a3f79059cfe55e8a1ec145d95ed3

CleanSpec.mk

@@ -47,3 +47,4 @@
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/bin/rild)

rild/Android.mk

@@ -18,6 +18,7 @@ endif # arm
 LOCAL_CFLAGS := -DRIL_SHLIB
 
 LOCAL_MODULE:= rild
+LOCAL_MODULE_TAGS := optional
 
 include $(BUILD_EXECUTABLE)