ACPICA: EFI/EDK2: Cleanup to enable /WX for MSVC builds

ACPICA commit a7c6d65a5dab20b1e191c197e09af337fc54b341

/WX turns warning into fatal erros for MSVC builds. We need /WX- during
EDK2 porting to allow agile development.

Now it is time to enable /WX and some explicit type conversion cleanups
are required for enabling /WX. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/a7c6d65a
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>

drivers/acpi/acpica/utprint.c

@@ -286,7 +286,7 @@ static char *acpi_ut_format_number(char *string,
 	/* Generate full string in reverse order */
 
 	pos = acpi_ut_put_number(reversed_string, number, base, upper);
-	i = ACPI_PTR_DIFF(pos, reversed_string);
+	i = (s32)ACPI_PTR_DIFF(pos, reversed_string);
 
 	/* Printing 100 using %2d gives "100", not "00" */
 
@@ -475,7 +475,7 @@ int vsnprintf(char *string, acpi_size size, const char *format, va_list args)
 			if (!s) {
 				s = "<NULL>";
 			}
-			length = acpi_ut_bound_string_length(s, precision);
+			length = (s32)acpi_ut_bound_string_length(s, precision);
 			if (!(type & ACPI_FORMAT_LEFT)) {
 				while (length < width--) {
 					pos =
@@ -579,7 +579,7 @@ int vsnprintf(char *string, acpi_size size, const char *format, va_list args)
 		}
 	}
 
-	return (ACPI_PTR_DIFF(pos, string));
+	return ((int)ACPI_PTR_DIFF(pos, string));
 }
 
 /*******************************************************************************