some more regex portability fixes

[Ulrich Drepper]

Aharon Robbins wrote:
> Hi.  Here are some regex portability fixes, primarily from Nelson Beebe
> who likes to compile gawk with over 40 system+compiler combinations.

I've applied the patch but

~ some code didn't follow the coding conventions

~ the changelog entry format is wrong

~ the regcomp.c patch is missing

-- 
➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖