ocfs2: Allocate discontiguous block groups.

If we cannot get a contiguous region for a block group, allocate a
discontiguous one when the filesystem supports it.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Tao Ma <tao.ma@oracle.com>

diff --cc fs/ocfs2/ocfs2.h
Simple merge

diff --cc fs/ocfs2/ocfs2_fs.h
Simple merge

diff --cc fs/ocfs2/suballoc.c
Simple merge