Write CodeView information about static locals in optimized code

Write CodeView S_LDATA32 symbols for static locals in optimized code. We have
to handle these separately, as they come after the S_FRAMEPROC, plus you can't
have S_BLOCK32 symbols like you can in unoptimized code.

gcc/
	* dwarf2codeview.cc (write_optimized_static_local_vars): New function.
	(write_function): Call write_optimized_static_local_vars.