Fix filter rule when checking for apks in PRODUCT_COPY_FILES.

PRODUCT_COPY_FILES entries can include the src:dest:owner
syntax versus src:dest. This causes the filter to miss
certain cases. Instead use the word-colon function to
grab the dest regardless of syntax.

Change-Id: I1f4e57a236c1db148bada0cfe5bd1e87bb1194d6
Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>