Add include_size check for preventing overflow

[7erryX]

CVE-2016-7163

opj_pi_create_decode in src/lib/openjp2/pi.c once caused Integer Overflow and was fixed in Commit c16bc05

Similar code snippet

opj_pi_initialise_encode in src/lib/openjp2/pi.c contains a similar logic (line 1698)

    /* memory allocation for include*/
    l_current_pi->include_size = l_tcp->numlayers * l_step_l;
    l_current_pi->include = (OPJ_INT16*) opj_calloc(l_current_pi->include_size,
                            sizeof(OPJ_INT16));

Would it make sense to add a similar check as the practice of defending programming?