[X86] Add patterns for rotr by immediate to fix PR41057.

Prior to the introduction of funnel shift intrinsics we could count on rotate
by immediates prefering to use rotl since that's what MatchRotate would check
first. The or+shift pattern doesn't have a direction so one must be chosen
arbitrarily.

With funnel shift, there is a direction and fshr will try to use rotr first.
While fshl will try to use rotl first.

This patch adds the isel patterns for rotr to complement the rotl patterns. I've
put the rotr by 1 patterns in the instruction patterns. And moved the rotl by
bitwidth-1 patterns to separate Pat patterns.

Fixes PR41057.

llvm-svn: 356121