ndk-build: fix parsing of libtool libraries for multi arch
ndk-build: fix parsing of libtool libraries for multi arch

The libtool-clear-vars rule was duplicated and the incorrect
one was being used so cached variables were not cleared and
the libtool libraries in the new root were not parsed.

cee1/cerbero-mac,cee1/cerbero-mac,cee1/cerbero-mac,cee1/cerbero-mac