ehea: fix skb_frag_size typo

Commit 9e903e085262 ("net: add skb frag size accessors") introduced a
typo in ehea driver.

Reported-by: Stephen Rothwell <[e-mail]>
Signed-off-by: Eric Dumazet <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/net/ethernet/ibm/ehea/ehea_main.c

···
 			sgentry = &sg_list[i - sg1entry_contains_frag_data];
 
 			sgentry->l_key = lkey;
-			sgentry->len = frag_size(frag);
+			sgentry->len = skb_frag_size(frag);
 			sgentry->vaddr = ehea_map_vaddr(skb_frag_address(frag));
 			swqe->descriptors++;
 		}