ACPICA: Rename variable to match upstream

There is a variable name mismatch in acpi_ut_strtoul_multiply64()
between the ACPICA code in the kernel and the corresponding upstream
code which may be problematic if changes to this particular piece of
code are made upstream and ported to Linux, so rename the variable
in question to match its name in the upstream code.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/acpica/utstrsuppt.c

@@ -370,7 +370,7 @@ acpi_ut_insert_digit(u64 *accumulated_value, u32 base, int ascii_digit)
 static acpi_status
 acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product)
 {
-	u64 val;
+	u64 product;
 	u64 quotient;
 
 	/* Exit if either operand is zero */
@@ -393,15 +393,15 @@ acpi_ut_strtoul_multiply64(u64 multiplicand, u32 base, u64 *out_product)
 		return (AE_NUMERIC_OVERFLOW);
 	}
 
-	val = multiplicand * base;
+	product = multiplicand * base;
 
 	/* Check for 32-bit overflow if necessary */
 
-	if ((acpi_gbl_integer_bit_width == 32) && (val > ACPI_UINT32_MAX)) {
+	if ((acpi_gbl_integer_bit_width == 32) && (product > ACPI_UINT32_MAX)) {
 		return (AE_NUMERIC_OVERFLOW);
 	}
 
-	*out_product = val;
+	*out_product = product;
 	return (AE_OK);
 }