MTP: Use fork instead of pthread

Change-Id: I95cf6f4def0c86f40c775738f0712323f0a0f146
update exfat from current head

Change-Id: I7d93474296612fda1dde23f6e8690668d6880e27
mktime_tz is blocking, don't use it

Change-Id: I0a66a69b68d975389302ae4361c9c106eb722538
MTP: fix some code paths

Still doesn't fix the bug of copying zip files to the root of
storage in Windows.

Change-Id: Iddec66a49c17cf48cbd1c67ad6679349ece8e05c
Merge remote-tracking branch 'omni/android-4.4' into kk4.4