[Ada] Missing escape of the double quote in JSON output

[Ada] Missing escape of the double quote in JSON output

In Ada, the name of operators contains a pair of double quotes, which
need to be properly escaped when the name appears in the JSON output of
-gnatR.

The change also ensures that formal parameters are not listed in the
layout information, since this information is not back-annotated for
them.

2019-07-09  Eric Botcazou  <ebotcazou@adacore.com>

gcc/ada/

	* repinfo.adb (List_Entities): Disregard formals altogether.
	(List_Name): Properly escape the double quote in the JSON
	output.

From-SVN: r273279