Fix matching table entry value. Use real table value instead of its index
in valuestate array.

When opcode has size equal to ipfw_insn_u32, this means that it should
additionally match value specified in d[0] with table entry value.
ipfw_table_lookup() returns table value index, use TARG_VAL() macro to
convert it to its value. The actual 32-bit value stored in the tag field
of table_value structure, where all unspecified u32 values are kept.

PR: 217262
Reviewed by: melifaro
MFC after: 1 week
Sponsored by: Yandex LLC