libnl: update to version 3.12

libnl: update to version 3.12

Changes: https://github.com/thom311/libnl/compare/libnl3_11_0...libnl3_12_0

The apk size did not increase much:
Old size for armsr/armv8:
   767 libnl200-3.11.0-r1.apk
 13480 libnl-cli200-3.11.0-r1.apk
 44511 libnl-core200-3.11.0-r1.apk
  9101 libnl-genl200-3.11.0-r1.apk
 32485 libnl-nf200-3.11.0-r1.apk
185723 libnl-route200-3.11.0-r1.apk

new size for armsr/armv8:
   764 libnl200-3.12.0-r1.apk
 13471 libnl-cli200-3.12.0-r1.apk
 45031 libnl-core200-3.12.0-r1.apk
  9098 libnl-genl200-3.12.0-r1.apk
 32479 libnl-nf200-3.12.0-r1.apk
193131 libnl-route200-3.12.0-r1.apk

Link: https://github.com/openwrt/openwrt/pull/21097
Signed-off-by: Hauke Mehrtens <[email protected]>