BACKPORT: f2fs: fix to handle segment allocation failure correctly

If CONFIG_F2FS_CHECK_FS is off, and for very rare corner case that
we run out of free segment, we should not panic kernel, instead,
let's handle such error correctly in its caller.

Signed-off-by: Chao Yu <chao@kernel.org>
Tested-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

(cherry picked from commit 7d009e048d7cfcc21d400f2aba4c8bacbdebbd47)
[drosen: Resolved many conflicts in segment.c ]
Change-Id: Ic3db543ed6012d4083c7d899bc3c83f310f78437
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Bug: 358293777