[bmv2 backend] meta data must be flat struct? about p4c HOT 3 CLOSED

// p4lang/p4c#118
#include<core.p4>
#include<v1model.p4>

typedef standard_metadata_t std_m;
struct H { };
struct M { std_m smeta; };

parser ParserI(packet_in pk, out H hdr, inout M meta, inout std_m smeta) {
    state start { transition accept; }
}

control VC(in H hdr, inout M meta) {
    apply { }
}

control Main(inout H hdr, inout M meta, inout std_m smeta) {
    // VC() vc;
    apply { 
        // vc.apply(hdr, meta);
        meta.smeta.drop = true;
    }
}

control CC(inout H hdr, inout M meta) {
    apply { }
}

control DeparserI(packet_out b, in H hdr) {
    apply { }
}

V1Switch(ParserI(), VC(), Main(), Main(), CC(), DeparserI()) main;