This commit is currently implementing supports for scalar cryptography extension for LLVM according to version v1.0.0 of K Ext specification(scala crypto has been ratified already). Currently, we are implementing the MC (Machine Code) layer of his extension and the majority of work is done under llvm/lib/Target/RISCV directory. There are also some test files in llvm/test/MC/RISCV directory.
Remove the subfeature of Zbk* which conflict with b extensions to reduce the size of the patch.
(Zbk* will be resubmit after this patch has been merged)