riscv: qspinlock: Allow force qspinlock from the command line

Allow cmdline to force the kernel to use queued_spinlock when
CONFIG_RISCV_COMBO_SPINLOCKS=y.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Guo Ren <guoren@kernel.org>