ipa-modref cleanup

ipa-modref cleanup

A small refactoring of ipa-modref to make it bit more
C++y by moving logic analyzing ssa name flags to a class
and I also moved the anonymous namespace markers so we do not
export unnecessary stuff.  There are no functional changes.

Bootstrapped/regtested x86_64-linux, will commit it shortly.

gcc/ChangeLog:

	* ipa-modref.c: Fix anonymous namespace placement.
	(class modref_eaf_analysis): New class.
	(analyze_ssa_name_flags): Turn to ...
	(modref_eaf_analysis::analyze_ssa_name): ... this one.
	(merge_call_lhs_flags): Turn to ...
	(modref_eaf_analysis::merge_call_lhs_flags): .. this one
	(modref_eaf_analysis::merge_with_ssa_name): New member function.
	(record_escape_points): Turn to ...
	(modref_eaf_analysis::record_escape_points): ... this one.
	(analyze_parms): Updat
	(ipa_merge_modref_summary_after_inlining): Move to the end of file.