target.def (output_source_filename): New hook.

target.def (output_source_filename): New hook.

	* target.def (output_source_filename): New hook.
	* doc/tm.texi.in (TARGET_ASM_OUTPUT_SOURCE_FILENAME): Document.
	* doc/tm.texi: Regenerate.
	* toplev.c (output_file_directive) Remove function.
	* toplev.h (output_file_directive) Remove.
	* output.h (default_asm_output_source_filename,
	output_file_directive): Declare.
	* varasm.h (default_asm_output_source_filename,
	output_file_directive): New functions.

	* config/mips/mips.h (ASM_OUTPUT_SOURCE_FILENAME): Remove macro.
	* config/mips/mips-protos.h (mips_output_filename): Remove.
	* config/mips/mips.c (mips_output_filename): Make Static.
	(TARGET_ASM_OUTPUT_SOURCE_FILENAME): Define.

From-SVN: r162542