ACPICA: Work around an ancient GCC bug.

warning: cast from function call of type 'char *' to non-matching type 'long unsigned int'

Since acpi_ut_format_number() hasn't been enabled for the Linux kernel,
this patch doesn't affect the Linux kernel.
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>

drivers/acpi/acpica/utprint.c

@@ -242,6 +242,7 @@ static char *acpi_ut_format_number(char *string,
 				   u64 number,
 				   u8 base, s32 width, s32 precision, u8 type)
 {
+	char *pos;
 	char sign;
 	char zero;
 	u8 need_prefix;
@@ -289,9 +290,8 @@ static char *acpi_ut_format_number(char *string,
 
 	/* Generate full string in reverse order */
 
-	i = ACPI_PTR_DIFF(acpi_ut_put_number
-			  (reversed_string, number, base, upper),
-			  reversed_string);
+	pos = acpi_ut_put_number(reversed_string, number, base, upper);
+	i = ACPI_PTR_DIFF(pos, reversed_string);
 
 	/* Printing 100 using %2d gives "100", not "00" */