xfstests: add _require_attrs

Add a new helper to check if extended attributes are supported.  It
errors out if any of the attr tools are not found, or if a filesystem
does not support setting attributes.

Remove the opencoded checks for the attr tools from various tests
now that we do them in common code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>

062

@@ -35,6 +35,7 @@ status=1	# failure is the default!
 # get standard environment, filters and checks
 . ./common.rc
 . ./common.filter
+. ./common.attr
 
 _cleanup()
 {
@@ -120,6 +121,8 @@ _supported_fs xfs udf nfs
 _supported_os Linux
 
 _require_scratch
+_require_attrs
+
 rm -f $tmp.backup1 $tmp.backup2 $seq.full
 
 # real QA test starts here