ACPICA: Cleanup for all string-to-integer conversions

ACPICA commit e2e72a351201fd58e4694418859ae2c247dafca0

Consolidate multiple versions of strtoul64 to one common version.
limit possible bases to either 10 or 16.
Handles both implicit and explicit conversions.
Added a 2-character ascii-to-hex function for GPEs and buffers.
Adds a new file, utstrtoul64.c

Link: https://github.com/acpica/acpica/commit/e2e72a35
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpica/exconcat.c b/drivers/acpi/acpica/exconcat.c
index 2423fe0..5429c2a 100644
--- a/drivers/acpi/acpica/exconcat.c
+++ b/drivers/acpi/acpica/exconcat.c
@@ -156,7 +156,7 @@
 
 		status =
 		    acpi_ex_convert_to_integer(local_operand1, &temp_operand1,
-					       16);
+					       ACPI_STRTOUL_BASE16);
 		break;
 
 	case ACPI_TYPE_BUFFER: