nouveau/ws: fix building error in nouveau_ws_push_dump()

nouveau/ws: fix building error in nouveau_ws_push_dump()

PRIxPTR macro solves the problem

Fixes the following build error:

../src/nouveau/winsys/nouveau_push.c:119:43: error: format specifies type 'unsigned long' but the argument has type 'int' [-Werror,-Wformat]
      printf("[0x%08lx] HDR %x subch %i", cur - push->orig_map, hdr, subchan);
                 ~~~~~                    ^~~~~~~~~~~~~~~~~~~~
                 %08x
1 error generated.

Reviewed-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24326>