Remove obsolete OpenBSD/MIPS support

Remove obsolete OpenBSD/MIPS support

	libgcc:
	* config.host (mips*-*-openbsd*): Remove.

	gcc:
	* config.gcc (mips*-*-openbsd*): Remove.
	* config/mips/openbsd.h: Remove.
	* config/mips/sdb.h: Remove.

	* config/mips/mips.h (SDB_OUTPUT_SOURCE_LINE): Remove.
	* config/mips/mips.c (sdb_label_count): Remove.
	(mips_debugger_offset): Remove #if 0 code.
	(mips_output_function_prologue) [SDB_DEBUGGING_INFO]: Remove.
	* config/mips/sde.h (SDB_DEBUGGING_INFO): Don't undef.

	contrib:
	* config-list.mk (LIST): Remove mips-openbsd.

From-SVN: r185245