Revert "Fix filter rule when checking for apks in PRODUCT_COPY_FILES."

# src:dest pair is the first one to match the same dest"

#$(1): the src:dest pair

define check-product-copy-files

$(if $(filter %.apk, $(call word-colon, 2, $(1))),$(error \

$(if $(filter %.apk, $(1)),$(error \

    Prebuilt apk found in PRODUCT_COPY_FILES: $(1), use BUILD_PREBUILT instead!))

endef

# filter out the duplicate <source file>:<dest file> pairs.