xfs: make some xfs project quota tests generic

This patch makes some xfs project quota tests generic,
so that there is at least some coverage on ext4 for this
(semi-)new feature.

It requires bleeding edge xfsprogs, so that xfs_quota and
xfs_io's chproj command can operate on "foreign" filesystems,
and requires relatively new e2fsprogs to enable the project
quota feature on-disk.

The mechanism for enabling project quota on ext4 is a bit
arcane, but hopefully I've encapsulated it reasonably well here.

Changes:

* look for "project" feature in _require_prjquota
* look for accounting not enforcement (-P) in _require_prjquota
* add a _scratch_enable_pquota to turn on project quota feature
* s/pquota/quota/ in _qmount_option for ext4
* add helper to test for xfs_io chproj on foreign filesystems
* switch from block to inode quota in xfs/133 because empty
  ext4 dirs consume one block
* cosmetic/generic changes for mkfs, require tests, etc.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

common/rc

@@ -2031,6 +2031,9 @@ _require_xfs_io_command()
 
 	testfile=$TEST_DIR/$$.xfs_io
 	case $command in
+	"chproj")
+		testio=`$XFS_IO_PROG -F -f -c "chproj 0" $testfile 2>&1`
+		;;
 	"falloc" )
 		testio=`$XFS_IO_PROG -F -f -c "falloc 0 1m" $testfile 2>&1`
 		;;
@@ -2062,6 +2065,8 @@ _require_xfs_io_command()
 		_notrun "xfs_io $command support is missing"
 	echo $testio | grep -q "Operation not supported" && \
 		_notrun "xfs_io $command failed (old kernel/wrong fs?)"
+	echo $testio | grep -q "foreign file active" && \
+		_notrun "xfs_io $command not supported on $FSTYP"
 
 	test -z "$param" && return
 	$XFS_IO_PROG -c "help $command" | grep -q "^ $param --" || \