[LV] Check isPredInst instead of isScalarWithPred in uniform analysis. (#98892)
Any instruction marked as uniform will result in a uniform
VPReplicateRecipe. If it requires predication, it will be placed in a
replicate region, even if isScalarWithPredication returns false.
Check isPredicatedInst instead of isScalarWithPredication to avoid
generating uniform VPReplicateRecipes placed inside a replicate region.
This fixes an assertion when using scalable VFs.
Fixes https://github.com/llvm/llvm-project/issues/80416.
Fixes https://github.com/llvm/llvm-project/issues/94328.
Fixes https://github.com/llvm/llvm-project/issues/99625.
PR: https://github.com/llvm/llvm-project/pull/98892