ACPICA commit 
7d9fd64397d7c38899d3dc497525f6e6b044e0e3
OSPMs like Linux expect an acpi_physical_address returning value from
acpi_find_root_pointer(). This triggers warnings if sizeof (acpi_size) doesn't
equal to sizeof (acpi_physical_address):
  drivers/acpi/osl.c:275:3: warning: passing argument 1 of 'acpi_find_root_pointer' from incompatible pointer type [enabled by default]
  In file included from include/acpi/acpi.h:64:0,
                   from include/linux/acpi.h:36,
                   from drivers/acpi/osl.c:41:
  include/acpi/acpixf.h:433:1: note: expected 'acpi_size *' but argument is of type 'acpi_physical_address *'
This patch corrects acpi_find_root_pointer().
Link: https://github.com/acpica/acpica/commit/7d9fd643
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 
  *
  ******************************************************************************/
 
-acpi_status __init acpi_find_root_pointer(acpi_size * table_address)
+acpi_status __init acpi_find_root_pointer(acpi_physical_address * table_address)
 {
        u8 *table_ptr;
        u8 *mem_rover;
                        physical_address +=
                            (u32) ACPI_PTR_DIFF(mem_rover, table_ptr);
 
-                       *table_address = physical_address;
+                       *table_address =
+                           (acpi_physical_address) physical_address;
                        return_ACPI_STATUS(AE_OK);
                }
        }
                    (ACPI_HI_RSDP_WINDOW_BASE +
                     ACPI_PTR_DIFF(mem_rover, table_ptr));
 
-               *table_address = physical_address;
+               *table_address = (acpi_physical_address) physical_address;
                return_ACPI_STATUS(AE_OK);
        }
 
 
 ACPI_EXTERNAL_RETURN_STATUS(acpi_status __init acpi_reallocate_root_table(void))
 
 ACPI_EXTERNAL_RETURN_STATUS(acpi_status __init
-                           acpi_find_root_pointer(acpi_size * rsdp_address))
-
+                           acpi_find_root_pointer(acpi_physical_address *
+                                                  rsdp_address))
 ACPI_EXTERNAL_RETURN_STATUS(acpi_status
-                           acpi_get_table_header(acpi_string signature,
-                                                 u32 instance,
-                                                 struct acpi_table_header
-                                                 *out_table_header))
+                            acpi_get_table_header(acpi_string signature,
+                                                  u32 instance,
+                                                  struct acpi_table_header
+                                                  *out_table_header))
 ACPI_EXTERNAL_RETURN_STATUS(acpi_status
                             acpi_get_table(acpi_string signature, u32 instance,
                                            struct acpi_table_header