fat: notify when discard is not supported
fat: notify when discard is not supported

Change fatfs so that a warning is emitted when an attempt is made to mount
a filesystem with the unsupported `discard' option.

ext4 aready does this: http://patchwork.ozlabs.org/patch/192668/

Signed-off-by: Namjae Jeon <4eaf47c25ead9675aad93689a157e819ffdaf8b3@gmail.com>
Signed-off-by: Amit Sahrawat <5cf56165005f1156bda29b0d8857b2f7c7c1924e@gmail.com>
Acked-by: OGAWA Hirofumi <1dd685eef08048be95744a1b104ca593a93cc914@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas