forked from Mirrors/opensbi

The CSR encoding for t-head c9xx cores is shared across all the platforms with these cores. So move header thead_c9xx.h to the thead subdir. Signed-off-by: Inochi Amaoto <inochiama@outlook.com> Acked-by: Guo Ren <guoren@kernel.org> Reviewed-by: Anup Patel <anup@brainfault.org>