net: Fix build warnings after mac_header and transport_header became __u16.

net/core/skbuff.c: In function ‘__alloc_skb_head’:
net/core/skbuff.c:203:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c: In function ‘__alloc_skb’:
net/core/skbuff.c:279:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c:280:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c: In function ‘build_skb’:
net/core/skbuff.c:348:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c:349:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]

Signed-off-by: David S. Miller <[e-mail]>

net/core/skbuff.c

···
 	atomic_set(&skb->users, 1);
 
 #ifdef NET_SKBUFF_DATA_USES_OFFSET
-	skb->mac_header = ~0U;
+	skb->mac_header = (__u16) ~0U;
 #endif
 out:
 	return skb;
···
 	skb_reset_tail_pointer(skb);
 	skb->end = skb->tail + size;
 #ifdef NET_SKBUFF_DATA_USES_OFFSET
-	skb->mac_header = ~0U;
-	skb->transport_header = ~0U;
+	skb->mac_header = (__u16) ~0U;
+	skb->transport_header = (__u16) ~0U;
 #endif
 
 	/* make sure we initialize shinfo sequentially */
···
 	skb_reset_tail_pointer(skb);
 	skb->end = skb->tail + size;
 #ifdef NET_SKBUFF_DATA_USES_OFFSET
-	skb->mac_header = ~0U;
-	skb->transport_header = ~0U;
+	skb->mac_header = (__u16) ~0U;
+	skb->transport_header = (__u16) ~0U;
 #endif
 
 	/* make sure we initialize shinfo sequentially */