net: fix a wrong assignment in skb_split()

commit c9af6db4c11ccc6c3e7f1 (net: Fix possible wrong checksum generation)
has a suspicous piece:

	-       skb_shinfo(skb1)->gso_type = skb_shinfo(skb)->gso_type;
	-
	+       skb_shinfo(skb)->tx_flags = skb_shinfo(skb1)->tx_flags & SKBTX_SHARED_FRAG;

skb1 is the new skb, therefore should be on the left side of the assignment.
This patch fixes it.

Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>