[AArch64] Add index check before lowerInterleavedStore() uses ShuffleVectorInst's mask

This commit fixes https://github.com/llvm/llvm-project/issues/57326.

Currently we would take a Mask out and directly use it by doing
auto Mask = SVI->getShuffleMask();
However, if the mask is undef, this Mask is not initialized. It might be
a vector of -1 or random integers.
This would cause an Out-of-bound read later when trying to find a
StartMask.

This change checks if all indices in the Mask is in the allowed range,
and fixes the out-of-bound accesses.

Differential Revision: https://reviews.llvm.org/D132634