[ARC] [LRA] Avoid emitting COND_EXEC during expand.

[ARC] [LRA] Avoid emitting COND_EXEC during expand.

Emmitting COND_EXEC rtxes during expand does introduces errors due to LRA handling of them. Issue discovered while running dejagnu test suit with mlra option on.

gcc/
2017-07-17  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/arc/arc.md (clzsi2): Expand to an arc_clzsi2 instruction
	that also clobbers the CC register. The old expand code is moved
	to ...
	(*arc_clzsi2): ... here.
	(ctzsi2): Expand to an arc_ctzsi2 instruction that also clobbers
	the CC register. The old expand code is moved to ...
	(arc_ctzsi2): ... here.

From-SVN: r250275