Revert r331819 [GlobalISel][Legalizer] More concise and faster widenScalar, NFC

Reverting this to see if the clang-cmake-aarch64-global-isel and
clang-cmake-aarch64-quick bots are failing because of this commit

llvm-svn: 331839
GitOrigin-RevId: 27bba4495a21034651d559f0bbeeb6c4da71bc54
6 files changed