net: Increase the size of skb_frag_t

To increase commonality between block and net, we are going to replace
the skb_frag_t with the bio_vec.  This patch increases the size of
skb_frag_t on 32-bit machines from 8 bytes to 12 bytes.  The size is
unchanged on 64-bit machines.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/skbuff.h

@@ -314,13 +314,8 @@ struct skb_frag_struct {
 	struct {
 		struct page *p;
 	} page;
-#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
 	__u32 page_offset;
 	__u32 size;
-#else
-	__u16 page_offset;
-	__u16 size;
-#endif
 };
 
 /**