JFS: add uid, gid, and umask mount options

OS/2 doesn't initialize the uid, gid, or unix-style permission bits.  The
uid, gid, & umask mount options perform pretty much like those for the fat
file system, overriding what is stored on disk.  This is useful for users
sharing the file system with OS/2.

I implemented a little feature so that if you mask the execute bit, it
will be re-enabled on directories when the appropriate read bit is unmasked.
I didn't want to implement an fmask & dmask option.

Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>

fs/jfs/acl.c

@@ -183,6 +183,9 @@ cleanup:
 		posix_acl_release(acl);
 	} else
 		inode->i_mode &= ~current->fs->umask;
+	
+	JFS_IP(inode)->mode2 = (JFS_IP(inode)->mode2 & 0xffff0000) |
+			       inode->i_mode;
 
 	return rc;
 }