staging: r8188eu: remove set but unused variable from rtl8188e_Add_RateATid

Remove set but unused variable init_rate from the rtl8188e_Add_RateATid
function in hal/rtl8188eu_cmd.c, as this fixes a kernel test robot
warning. Removing the call to get_highest_rate_idx has no side effects
here so is safe.
Reported-by: Nkernel test robot <lkp@intel.com>
Acked-by: NMichael Straube <straube.linux@gmail.com>
Signed-off-by: NPhillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210816234459.132239-2-phil@philpotter.co.ukSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/hal/rtl8188e_cmd.c

@@ -155,7 +155,7 @@ void rtl8188e_Add_RateATid(struct adapter *pAdapter, u32 bitmap, u8 arg, u8 rssi
 {
 	struct hal_data_8188e *haldata = GET_HAL_DATA(pAdapter);
 
-	u8 macid, init_rate, raid, shortGIrate = false;
+	u8 macid, raid, shortGIrate = false;
 
 	macid = arg & 0x1f;
 
@@ -167,13 +167,8 @@ void rtl8188e_Add_RateATid(struct adapter *pAdapter, u32 bitmap, u8 arg, u8 rssi
 
 	bitmap |= ((raid << 28) & 0xf0000000);
 
-	init_rate = get_highest_rate_idx(bitmap & 0x0fffffff) & 0x3f;
-
 	shortGIrate = (arg & BIT(5)) ? true : false;
 
-	if (shortGIrate)
-		init_rate |= BIT(6);
-
 	raid = (bitmap >> 28) & 0x0f;
 
 	bitmap &= 0x0fffffff;