Fix PR 110554: vec lowering introduces scalar signed-boolean:32 comparisons

Fix PR 110554: vec lowering introduces scalar signed-boolean:32 comparisons

So the problem is vector generic decided to do comparisons in signed-boolean:32
types but the rest of the middle-end was not ready for that. Since we are building
the comparison which will feed into a cond_expr here, using boolean_type_node is
better and also correct. The rest of the compiler thinks the ranges for
comparison is always [0,1] too.

Note this code does not currently lowers bigger vector sizes into smaller
vector sizes so using boolean_type_node here is better.

OK? bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	PR middle-end/110554
	* tree-vect-generic.cc (expand_vector_condition): For comparisons,
	just build using boolean_type_node instead of the cond_type.
	For non-comparisons/non-scalar-bitmask, build a ` != 0` gimple
	that will feed into the COND_EXPR.