[LV] Add cost model for simd vector select instructions of type float

For simd vector selects, use cmeq + bsl for v2f32/v4f32/v2f64, so their cost are cheep.
Fix https://github.com/llvm/llvm-project/issues/63082

Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D152523