ng_fec_input defined 2 params but assigned to 4-param if_input slot: calling-convention UB

Summary

ng_fec_input(:862-863) defined as 2-param (ifp,m0). if_input slot type(if_var.h:354-356) is 4-param (ifp,m,pktinfo,cpuid). Line :443 assigns 2-arg fn to 4-arg slot. HW RX drivers call ifp->if_input(ifp,m,pi,cpuid)(if_var.h:67). Incompatible pointer type UB C11 6.5.2.2. x86-64 silently ignores extra args. Stack-passing ABI -> caller pushes 4, callee pops 2 -> frame corruption. Fix: add 2 missing params to match if_input signature.