f2fs: issue discard commands if gc_urgent is set

commit 5f656541ff6e4f58b4ab5b4ae59badb97a9ff749 upstream.

It's time to issue all the discard commands, if user sets the idle time.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Git-commit: b85f2477
Git-repo: https://android.googlesource.com/kernel/common.git


Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>