ACPICA: Rename acpi_hw_gpe_register_bit

Rename acpi_hw_gpe_register_bit to acpi_hw_get_gpe_register_bit
in order to be same with ACPICA code base.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>