For floating point vector compares the target mode is an integer mode
which accidently was used as register mode when forcing the compare
operands into regs.

gcc/ChangeLog:

	* config/s390/s390.c (s390_expand_vcond): Use the compare operand
	mode.

gcc/testsuite/ChangeLog:

	* gcc.target/s390/vector/vec-vcond-1.c: New test.

From-SVN: r233552