[Ada] Add support for PE-COFF PIE to System.Dwarf_Line

[Ada] Add support for PE-COFF PIE to System.Dwarf_Line

gcc/ada/

	* adaint.c (__gnat_get_executable_load_address): Add Win32 support.
	* libgnat/s-objrea.ads (Get_Xcode_Bounds): Fix typo in comment.
	(Object_File): Minor reformatting.
	(ELF_Object_File): Uncomment predicate.
	(PECOFF_Object_File): Likewise.
	(XCOFF32_Object_File): Likewise.
	* libgnat/s-objrea.adb: Minor reformatting throughout.
	(Get_Load_Address): Implement for PE-COFF.
	* libgnat/s-dwalin.ads: Remove clause for System.Storage_Elements
	and use consistent wording in comments.
	(Dwarf_Context): Set type of Low, High and Load_Address to Address.
	* libgnat/s-dwalin.adb (Get_Load_Displacement): New function.
	(Is_Inside): Call Get_Load_Displacement.
	(Low_Address): Likewise.
	(Open): Adjust to type change.
	(Aranges_Lookup): Change type of Addr to Address.
	(Read_Aranges_Entry): Likewise for Start and adjust.
	(Enable_Cach): Adjust to type change.
	(Symbolic_Address): Change type of Addr to Address.
	(Symbolic_Traceback): Call Get_Load_Displacement.