[GOFF][z/OS] Change PrivateGlobalPrefix and PrivateLabelPrefix to be L# (#85730)
The current values for PrivateGlobalPrefix and PrivateLabelPrefix (@@
and @ respectively) are, in hindsight, poor choices for multiple
reasons:
First, there exist externally visible routines from the language
environment that begin with @@. These functions are certainly not
local/private by any means and they should not share a prefix with
private globals.
Secondly, both private globals and private labels should be handled the
same way by GOFF, so it doesn't make much sense for them to have
separate prefixes. GOFF remains the only file format where these are
different and there is no reason for that to be the case
llvm-project
5fb2797f - [GOFF][z/OS] Change PrivateGlobalPrefix and PrivateLabelPrefix to be L# (#85730)
