xfs: propagate errors from xfs_rtginode_load

xfs: propagate errors from xfs_rtginode_load

xfs_rtginode_ensure() treats every xfs_rtginode_load() error other than
-ENOENT as success.  This can leave the realtime group inode unset after an
I/O, allocation, or corruption error.  Growfs then continues as though the
inode had been loaded.

Only -ENOENT means that the inode needs to be created.  Return all other
errors to the growfs caller.

Fixes: ae897e0bed0f ("xfs: support creating per-RTG files in growfs")
Cc: stable@vger.kernel.org
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>