fstests: make xfs_io mandatory

_test_inode_flag() and _test_inode_extsz() use "which $XFS_IO_PROG"
to check if xfs_io command is available. And "-i" option was added
to XFS_IO_PROG varibable by commit 54659ecdb5 ("fstests: run
xfs_io with -i option if supported"). So the command becomes "which
/usr/sbin/xfs_io -i", and it stops and waits for input from stdin,
because "-i" option of "which" means "Read aliases from stdin".

I've seen xfs/008 hang when testing with latest xfsprogs, where
xfs_io has "-i" support.

Fix it by removing the xfs_io command detections, and making xfs_io
mandatory in common/config.

Also fix the indentions in these functions, use tab instead of
spaces, while we're at it.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

common/rc

@@ -2911,30 +2911,26 @@ _populate_fs()
 #
 _test_inode_flag()
 {
-    flag=$1
-    file=$2
+	flag=$1
+	file=$2
 
-    if which $XFS_IO_PROG >/dev/null; then
-        if $XFS_IO_PROG -r -c 'lsattr -v' "$file" | grep -q "$flag" ; then
-	    return 0
-        fi
-    fi
-    return 1
+	if $XFS_IO_PROG -r -c 'lsattr -v' "$file" | grep -q "$flag" ; then
+		return 0
+	fi
+	return 1
 }
 
 # query the given files extsize allocator hint in bytes (if any)
 #
 _test_inode_extsz()
 {
-    file=$1
-    blocks=""
+	file=$1
+	blocks=""
 
-    if which $XFS_IO_PROG >/dev/null; then
 	blocks=`$XFS_IO_PROG -r -c 'stat' "$file" | \
 		awk '/^xattr.extsize =/ { print $3 }'`
-    fi
-    [ -z "$blocks" ] && blocks="0"
-    echo $blocks
+	[ -z "$blocks" ] && blocks="0"
+	echo $blocks
 }
 
 # scratch_dev_pool should contain the disks pool for the btrfs raid