blkid: Add support for probing exFAT

 * e2fsprogs can't currently detect exFAT filesystems.
 * Apply patch from GoogleTV to add support.

Change-Id: Ib08bdb1d13e995d133a62539e3bfa0e3a22eeead
Fix blkid time diff bug, build binary.

When calculating time diffs, use difftime() instead of risking
integer overflow.  Also build a "blkid" binary.

Bug: 11175082
Change-Id: I23521f45204574bb32f152926401c2cbad93175b
Merge tag 'android-4.4_r1' into cm-11.0

Android 4.4 Release 1.0
Merge tag 'android-4.4.1_r1' into kitkat

Android 4.4.1 Release 1