fstests: Make ./new work for non-root user

Currently 'new' script sources common/config which tries to find
mkfs and fails if not found (which is likely for non-root user).
This is inconvenient as development usually does not happen as root.
In fact the vast majority of setup in common/config and common/rc is
not necessary for 'new'. Split out the necessary bits into new
common/test_names and use it in 'new'. Cleanup common/rc and
common/config now that they're only used from 'check' and 'setup'.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

common/config

@@ -47,6 +47,8 @@
 #   validity or mountedness.
 #
 
+. common/test_names
+
 # all tests should use a common language setting to prevent golden
 # output mismatches.
 export LANG=C
@@ -269,11 +271,6 @@ fi
 rm -f /tmp/crc_check.img
 export XFS_MKFS_HAS_NO_META_SUPPORT
 
-# new doesn't need config file parsed, we can stop here
-if [ "$iam" == "new" ]; then
-	return 0
-fi
-
 _mount_opts()
 {
 	case $FSTYP in