r300g: avoid the use of goto

I was being lazy on Sunday morning, Droste on irc called me on it ;-)

src/gallium/drivers/r300/r300_emit.c

@@ -1105,10 +1105,8 @@ void r300_emit_dirty_state(struct r300_context* r300)
     /* Make sure we have at least 2*1024 spare dwords. */
     /* XXX It would be nice to know the number of dwords we really need to
      * XXX emit. */
-again:
-    if (!r300->winsys->check_cs(r300->winsys, dwords)) {
+    while (!r300->winsys->check_cs(r300->winsys, dwords)) {
         r300->context.flush(&r300->context, 0, NULL);
-	goto again;
     }
 
     if (r300->dirty_state & R300_NEW_QUERY) {