arch-riscv: Added the Zbs bitmanip instructions
arch-riscv: Added the Zbs bitmanip instructions

Added the bclr, bclri, bext, bexti, binv, binvi, bset, bseti
instructions.

Changes based on spec:
https://github.com/riscv/riscv-bitmanip/releases/download/1.0.0/bitmanip-1.0.0.pdf

Change-Id: I126d659d973b250b642bd56b3b149f0ee6a3323e
Signed-off-by: Jerin Joy <c7d56fc0723a766824f554c4d00f28ea16c2c36b@rivosinc.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/58632
Reviewed-by: Luming Wang <6cf1f09365b4faf18ce9aa4e5707c3307d436259@126.com>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Jason Lowe-Power <92de577f37050ad05b60626d2f17913f40dcb1a2@gmail.com>
Maintainer: Jason Lowe-Power <92de577f37050ad05b60626d2f17913f40dcb1a2@gmail.com>

gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5