RISC-V: Declare per cpu boot data as static

RISC-V: Declare per cpu boot data as static

commit f1de125766d6f377a4b5d5821bc12928f929a4eb upstream.

The per cpu boot data is only used within the cpu_ops_sbi.c. It can
be delcared as static.

Fixes: 9a2451f18663 ("RISC-V: Avoid using per cpu array for ordered booting")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>