libeth: xdp: access ->pp through netmem_desc instead of page

To eliminate the use of struct page in page pool, the page pool users
should use netmem descriptor and APIs instead.

Make xdp access ->pp through netmem_desc instead of page.

Signed-off-by: Byungchul Park <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Byungchul Park

include/net/libeth/xdp.h

@@ -1292,7 +1292,7 @@ static inline void libeth_xdp_prepare_buff(struct libeth_xdp_buff *xdp,
 	xdp_init_buff(&xdp->base, fqe->truesize, xdp->base.rxq);
 #endif
 	xdp_prepare_buff(&xdp->base, page_address(page) + fqe->offset,
-			 page->pp->p.offset, len, true);
+			 pp_page_to_nmdesc(page)->pp->p.offset, len, true);
 }
 
 /**