[clang] [clang][x86] Ensure we use the shifted value bit width to check for out of bounds per-element shift amounts (PR #156019)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

Out of range tests are already in place, and there was no difference for this as per-element shifts have the same types for both operands. The shift by immediate code that used it later had their own tests for out of bounds as well. 

https://github.com/llvm/llvm-project/pull/156019