ada: Fix crash with -gnatyB and -gnatdJ

ada: Fix crash with -gnatyB and -gnatdJ

The crash this patch fixes happened because calling the Errout.Error_Msg
procedures that don't have an N parameter is not allowed when not
parsing and -gnatdJ is on. And -gnatyB style checks are not emitted during
parsing but during semantic analysis.

This commit moves Check_Boolean_Operator from Styleg to Style so it can
call Errout.Error_Msg with a Node_Id parameter. This change of package
makes sense because:

1. The compiler is currently the only user of Check_Boolean_Operator.
2. Other tools don't do semantic analysis, and so cannot possibly
know when to use Check_Boolean_Operator anyway.

gcc/ada/

	* styleg.ads (Check_Boolean_Operator): Moved ...
	* style.ads (Check_Boolean_Operator): ... here.
	* styleg.adb (Check_Boolean_Operator): Moved ...
	* style.adb (Check_Boolean_Operator): ... here. Also add node
	parameter to call to Errout.Error_Msg.