ueventd fixup_sys_perms: fixup SELinux labels unconditionally

Currently, the fixup code in fixup_sys_perms() scans through all
entries in uevent*.rc. If it finds a match, then it performs a fixup.
If there's no match in that file, no fixup is performed.

SELinux file labels are independently stored in /file_contexts,
with no relationship to the files in /ueventd.rc. Even when no
entries exist in ueventd.rc, we still want to fixup the SELinux
file label in /sys when a uevent message occurs.

Change-Id: I0ccb5395ec0be9282095b844a5022e8c0d8903ac