page_pool: fix incorrect mp_ops error handling

Minor fix to the memory provider error handling, we should be jumping to
free_ptr_ring in this error case rather than returning directly.

Found by code-inspection.

Cc: skhawaja@google.com

Fixes: b400f4b8 ("page_pool: Set `dma_sync` to false for devmem memory provider")
Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Samiullah Khawaja <skhawaja@google.com>
Link: https://patch.msgid.link/20250821030349.705244-1-almasrymina@google.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>