weston-launch: Fix the typo for real this time

Thanks to MonkeyofDoom for point this out.  I'm still adjusting to the
fact that there's no 'd' in privilege, but I'll get over it.

src/weston-launch.c

@@ -635,7 +635,7 @@ main(int argc, char *argv[])
                     initgroups(wl.pw->pw_name, wl.pw->pw_gid) < 0 ||
 #endif
 		    setuid(wl.pw->pw_uid) < 0)
-			error(1, errno, "dropping priviledges failed");
+			error(1, errno, "dropping privileges failed");
 
 
 		if (sleep_fork) {