Use the DragonFly contrib patch system to correct improper sizeof(pointer)

Use the DragonFly contrib patch system to correct improper sizeof(pointer)
issues in vendor code.

BIND9:
    Allocated memory was not being entirely zerod out in a number of places.

LIBOPIE:
    An improper sizeof(pointer) just happened to work out to the same size
    as the 4-byte string it was really attempting to size, for 32 bit
    architectures.  Convert the pointer to an array to fix the problem.

DHCLIENT:
    An improper sizeof(pointer) just happened to work out to be the same
    size as the u_int32_t it was supposed to be getting the size of, for
    32 bit architectures.  Fixed.

    ICMP handling was calculating the incorrect packet offset due to
    a sizeof(ia) that should have been sizeof(*ia).

    In addition (unrelated to the original bug report), none of the
    patches for common/ were being applied.  They are now being applied.

TCPDUMP:
    OSPF6 parsing was completely broken, not only using an incorrect
    sizeof(pointer), but also misinterpreting the return value from
    ospf6_print_lsaprefix() which would result in an infinite loop.

References: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25702
Reported-by: Mark Eklund <meklund@cisco.com>