check: add ext4 group list when testing ext2 and ext3

Modern kernels use the ext4 implementation to support ext2 and ext3
mounts, and a number of the ext4 tests are actually suitable for
ext2 and ext3.  We're trying to move tests out of shared anyway, so
instead of moving tests from ext4/NNN to shared, let's just include
the ext4 group list when FSTYP is ext2 or ext3.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

check

@@ -130,6 +130,7 @@ get_group_list()
 	local grp=$1
 	local grpl=""
 	local sub=$(dirname $grp)
+	local fsgroup="$FSTYP"
 
 	if [ -n "$sub" -a "$sub" != "." -a -d "$SRC_DIR/$sub" ]; then
 		# group is given as <subdir>/<group> (e.g. xfs/quick)
@@ -138,7 +139,10 @@ get_group_list()
 		return
 	fi
 
-	for d in $SRC_GROUPS $FSTYP; do
+	if [ "$FSTYP" = ext2 -o "$FSTYP" = ext3 ]; then
+	    fsgroup=ext4
+	fi
+	for d in $SRC_GROUPS $fsgroup; do
 		if ! test -d "$SRC_DIR/$d" ; then
 			continue
 		fi