[RISCV] Add scheduler classes for the Zba and Zbb extensions.

I've used IALU for the simplest operations from Zbb:
min, minu, max, maxu, sext.b, sext.h, zext.h, andn, orn, xnor

I've put add.uw in IALU32 and slli.uw in ShiftImm32.

Remaining instructions have received new classes.
All 3 sh*add are grouped together. sh*add.uw are grouped together.
Rotate left and right are together. Everything else got their own
class containing one instruction.

I think what I have here is the minimum granularity we need. I
could be convinced that we need more classes.

Reviewed By: evandro

Differential Revision: https://reviews.llvm.org/D99040