lint-hunks: exit status for only affected lines

Prior to this patch, if there were any lint errors, this script would
exit with an error, even if those errors were not in the hunks being
tested by this script. This change makes it so that if any lint lines
are printed, an error is returned.

Change-Id: I69c8bef4367ccf25d287508f29e587b1f4426143
1 file changed