diagnostics: move diagnostic-macro-unwinding.{cc,h} -> diagnostics/macro-unwinding...

diagnostics: move diagnostic-macro-unwinding.{cc,h} -> diagnostics/macro-unwinding.{cc,h}

gcc/ChangeLog:
	* Makefile.in (OBJS): Replace diagnostic-macro-unwinding.o with
	diagnostics/macro-unwinding.o.
	* diagnostic-macro-unwinding.cc: Move to...
	* diagnostics/macro-unwinding.cc: ...here, moving content into
	namespace diagnostics.
	* diagnostic-macro-unwinding.h: Move to...
	* diagnostics/macro-unwinding.h: ...here, moving content into
	namespace diagnostics.
	* diagnostics/paths-output.cc: Update for move of
	"diagnostic-macro-unwinding.h" to "diagnostics/macro-unwinding.h".

gcc/c-family/ChangeLog:
	* c-opts.cc: Update for move of "diagnostic-macro-unwinding.h"
	to "diagnostics/macro-unwinding.h".

Signed-off-by: David Malcolm <dmalcolm@redhat.com>