staging: r8188eu: remove unnecessary variable in rtl8188eu_xmit

Return 0 directly instead of storing it in a variable.
This can prevent cocci warning as follows:

  Unneeded variable: "pull". Return "0" on line 298

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Kang Minchul <tegongkang@gmail.com>
Link: https://lore.kernel.org/r/20221025170621.271903-4-tegongkang@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/hal/rtl8188eu_xmit.c

@@ -149,7 +149,6 @@ static void fill_txdesc_phy(struct pkt_attrib *pattrib, __le32 *pdw)
 
 static s32 update_txdesc(struct xmit_frame *pxmitframe, u8 *pmem, s32 sz, u8 bagg_pkt)
 {
-	int	pull = 0;
 	uint	qsel;
 	u8 data_rate, pwr_status, offset;
 	struct adapter		*adapt = pxmitframe->padapter;
@@ -295,7 +294,7 @@ static s32 update_txdesc(struct xmit_frame *pxmitframe, u8 *pmem, s32 sz, u8 bag
 	ODM_SetTxAntByTxInfo_88E(&haldata->odmpriv, pmem, pattrib->mac_id);
 
 	rtl8188eu_cal_txdesc_chksum(ptxdesc);
-	return pull;
+	return 0;
 }
 
 /* for non-agg data frame or  management frame */