fix lib64 handling for 64bit targets

For 64bit targets, make sure we use /usr/lib64 instead of /usr/lib.

The binding between "is 64bit" and "use lib64" is kind of broken, but
Android doesn't really support multiple ABIs cleanly, so this is fine
until it does.

Change-Id: I3dcd7ee50bac08d4b72af793b37c6031c6890611
6 files changed