In BSD grep, fix escape map building in the regex parser. It was
previously using memory not explicitly initialized, and the MBS escape
map was being built based on a version of the pattern with escapes
already parsed out.
This is Kyle's change, but I restored the broken style that already
exists in this file.
Submitted by: Kyle Evans <kevans91 at ksu.edu>
Reviewed by: cem, Kyle Evans (my style changes)
Differential Revision: https://reviews.freebsd.org/D10098
41e04e8c77