mfd: intel-m10-bmc: Create m10bmc_sys_update_bits()

Wrap regmap_update_bits() with m10bmc_sys_update_bits() in order to be
able to add additional checks into it.

Co-developed-by: Russ Weight <russell.h.weight@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230417092653.16487-3-ilpo.jarvinen@linux.intel.com