staging: rtl8723au: rtl8723a_hal_init: Improve code readability

This patch improves code readability in the function
rtl8723a_cal_txdesc_chksum.  It improves the readability of the argument
of the function le16_to_cpu.
Signed-off-by: Johannes Postma <jgmpostma@gmail.com>
Acked-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723au/hal/rtl8723a_hal_init.c

@@ -1847,7 +1847,7 @@ static void rtl8723a_cal_txdesc_chksum(struct tx_desc *ptxdesc)
 	ptxdesc->txdw7 &= cpu_to_le32(0xffff0000);
 
 	for (index = 0; index < count; index++)
-		checksum ^= le16_to_cpu(*(usPtr + index));
+		checksum ^= le16_to_cpu(usPtr[index]);
 
 	ptxdesc->txdw7 |= cpu_to_le32(checksum & 0x0000ffff);
 }