Remove casts, make some whitespace changes in generated code.

This is the part of this change from Samba:

    commit f0a6043fb201940f438f63c809df7186aa307f01
    Author: Matthieu Patou <mat@matws.net>
    Date:   Sun Oct 5 18:25:27 2014 -0700

    pidl-wireshark: handle 8 bits enum and change the signature of enum function to pass the exact type

    Instead of passing a uint32 in all cases we pass the exact type

    Pair-Programmed-With: Stefan Metzmacher <metze@samba.org>

that wasn't already in our version.

Change-Id: I7da99cb701c2eedadeb8acb68d32f657dfa85e5b
Reviewed-on: https://code.wireshark.org/review/5097
Reviewed-by: Guy Harris <guy@alum.mit.edu>