Allow enabling of dummy error_strerror() to support some use-cases

Enable a dummy error function to make use of error_strerror() in
third party libraries easier.

Disable if you run into name conflicts and want to really remove the
error_strerror()
(cherry picked from commit 8fe40dcd7d3b46193f74032361efb674112ee9e5)

Conflicts:
	ChangeLog
	programs/util/strerror.c
3 files changed