arc: Don't use predicated vadd2 instructions in mov patterns.

arc: Don't use predicated vadd2 instructions in mov patterns.

Update movdi, movdf and mov vectors not to use predicated vadd2
instructions. vadd2 is used as a "fast" move in these patterns. This
fixes a number of failures in dejagnu.

gcc/
2020-12-29  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/arc/arc.md (movdi_insn): Update pattern, no predicated
	vadd2 usage.
	(movdf_insn): Likewise.
	* config/arc/simdext.md (movVEC_insn): Likewise.

Signed-off-by: Claudiu Zissulescu <claziss@synopsys.com>