sparc.c:save_regs() offsets passed to dwarf2 code

[Joern Rennecke]

> I think all the functions exported by dwarf2out.c should be placed
> into a header file, so this nonsense need not be addressed ever again,
> and the next person on a 64-bit port using dwarf2 need not hit all the
> headaches I have over the past few days. ;-)

This means to desupport old-style K&R compilers for targets where int and
long are different.  If you want to support K&R, you rather have to
explicitly pass values of the correct type.