kernel: bump 4.4 to 4.4.112

kernel: bump 4.4 to 4.4.112

Refresh patches.
Remove upstreamed patches:

target/linux/generic/patches-4.4/030-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch
target/linux/generic/patches-4.4/030-3-cx82310_eth-use-skb_cow_head-to-deal-with-cloned-skb.patch
target/linux/generic/patches-4.4/030-4-sr9700-use-skb_cow_head-to-deal-with-cloned-skbs.patch
target/linux/generic/patches-4.4/030-5-lan78xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch

CVEs completely or partially addressed:

CVE-2017-5715
CVE-2017-5753
CVE-2017-17741
CVE-2017-1000410

Compile-tested: ar71xx Archer C7 v2
Run-tested: ar71xx Archer C7 v2

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>