BACKPORT: f2fs: fix to check return value __allocate_new_segment

__allocate_new_segment may return error when get_new_segment
fails, so its caller should check its return value.

Bug: 337626258
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
(cherry picked from commit ca702aed)
[xiuhong: Resolved minor conflict in fs/f2fs/f2fs.h]
Change-Id: Ia9fdd89b41f53a4cd12ba719393e4759b0b6136a
Signed-off-by: Xiuhong Wang <xiuhong.wang@unisoc.com>