* doc/invoke.texi: Document -minmax for 68HC12.

	* config/m68hc11/m68hc11.md ("umaxqi3"): Use TARGET_MIN_MAX.
	("uminqi3"): Likewise.
	("uminhi3", "umaxhi3"): Likewise.

	* config/m68hc11/m68hc11.h (MASK_MIN_MAX): Define.
	(TARGET_MIN_MAX): Define.
	(TARGET_SWITCHES): New option -minmax/-mnominmax.

From-SVN: r56284