mount.sh mounts all partitions with -o sync, which is bad for system
performance.
(From OE-Core rev: d49cf73754150b50a911d326aaa666f5da78855c)
(From OE-Core rev: 44c102386c9bca17743d2edd1f94d4071974204d)
Signed-off-by: Jesse Zhang <sen.zhang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>