wrong stabs offsets for invisible-reference arguments on mips eabi

[Eric Christopher]

This really does fix some gdb failures if someone could approve it. :)

-eric

> Index: gcc/ChangeLog
> from  Alexandre Oliva  <aoliva@redhat.com>
> 
> 	* dbxout.c (dbxout_parms): Apply DEBUGGER_ARG_OFFSET to parameters
> 	passed by invisible reference.

-- 
I will not use abbrev.