[GFS2] Need to ensure that sector_t is 64bits for GFS2

We need to ensure that sector_t is 64bits for GFS2, so that we need to
depend on LBD as well as LSF.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

fs/gfs2/Kconfig

 config GFS2_FS
 	tristate "GFS2 file system support"
-	depends on EXPERIMENTAL && (64BIT || LSF)
+	depends on EXPERIMENTAL && (64BIT || (LSF && LBD))
 	select FS_POSIX_ACL
 	select CRC32
 	help