pidl: check the size of pulled arrays of arrays

pidl: check the size of pulled arrays of arrays

We were accidentally checking the memory just past the array instead of
checking each member.

This could have led to the size of some arrays not being checked.

Found by Michael Hanselmann using Honggfuzz and an fuzzer for Samba's
NDR layer.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13877

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Pair-programmed-with: Andrew Bartlett <abartlet@samba.org>
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>