RISC-V: Add support fo the zihintpause extension

This was recently added to binutils and with any luck will soon be in
Linux, without it sparse will fail when trying to build new kernels on
systems with new toolchains.

Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
I re-indented the other extensions to match, and this one is on top of
the Zicbom patch as I figured that'd be easier.
1 file changed