[illumos-Developer] webrev: 878 regerror() error messages not i18n compliant

[Garrett D'Amore]

  http://mexico.purplecow.org/gdamore/webrev/regerror/

This addresses a problem that the regerror() messages are not localized 
properly.  I also discovered that the regerror_msg.h file was left over 
from a legacy implementation, and have removed it.  (This was not a 
public header file, but used internally in libc.)

Thanks.

     - Garrett