[RISCV] Generalize select (and (x , 0x1) == 0), y, (z ^ y) ) and select (and...

[RISCV] Generalize select (and (x , 0x1) == 0), y, (z ^ y) ) and select (and (x , 0x1) == 0), y, (z | y) ) transforms by removing and-clause

These transforms were recently added (by me) in D134881. Looking at the code again, I realized we don't need the (and x, 0x1) portion of the pattern, we just need to know that the result of that sub-tree is either 0 or 1. Checking for this directly allows us to match slightly more broadly. The test changes are zext i1 arguments, but this could also kick in for e.g. shifts of high bits, or any other source of known bits.

Differential Revision: https://reviews.llvm.org/D135081