releasetools: Modify regex for radio files

The filesmap file may contain additional information (such as a
sha1 hash) after the parition name. We should still work in these
cases, but can ignore the additional data.

Change-Id: I0feaa5e94d48fa94b66b6c07e1946674fe703d85
Merge remote-tracking branch 'cm/cm-11.0' into cm-11.0