sit: fix invalid declaration of rtnl_link_sit_get_proto() in sit.h
sit: fix invalid declaration of rtnl_link_sit_get_proto() in sit.h

Fixes: d715b8a5f6ec8faf205ae77950a1c625440be22f

Signed-off-by: Thomas Haller <16e26612e4159990a6b3691e92592e691ff74132@redhat.com>

dsahern/libnl,tklauser/libnl,HolyShitMan/libnl-1,HolyShitMan/libnl-1,dsahern/libnl,thom311/libnl,tklauser/libnl,greearb/libnl-ct,tklauser/libnl,HolyShitMan/libnl-1,dsahern/libnl,greearb/libnl-ct,greearb/libnl-ct,thom311/libnl,HolyShitMan/libnl-1,thom311/libnl,dsahern/libnl,tklauser/libnl