staging: r8188eu: remove empty function rtl8188eu_free_xmit_priv

Remove empty function rtl8188eu_free_xmit_priv from hal/rtl8188eu_xmit.c
and its declaration from include/rtl8188e_xmit.h, as well as the one
place where it is stored in the free_xmit_priv function pointer of the
HalFunc struct inside padapter. This is safe, as the wrapper function
checks for NULL before calling this function via the function pointer.
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210818234253.208271-5-phil@philpotter.co.ukSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/hal/rtl8188eu_xmit.c

@@ -19,10 +19,6 @@ s32	rtl8188eu_init_xmit_priv(struct adapter *adapt)
 	return _SUCCESS;
 }
 
-void	rtl8188eu_free_xmit_priv(struct adapter *adapt)
-{
-}
-
 static u8 urb_zero_packet_chk(struct adapter *adapt, int sz)
 {
 	u8 set_tx_desc_offset;

drivers/staging/r8188eu/hal/usb_halinit.c

@@ -2243,7 +2243,6 @@ void rtl8188eu_set_hal_ops(struct adapter *adapt)
 	halfunc->inirp_deinit = &rtl8188eu_inirp_deinit;
 
 	halfunc->init_xmit_priv = &rtl8188eu_init_xmit_priv;
-	halfunc->free_xmit_priv = &rtl8188eu_free_xmit_priv;
 
 	halfunc->init_recv_priv = &rtl8188eu_init_recv_priv;
 	halfunc->free_recv_priv = &rtl8188eu_free_recv_priv;

drivers/staging/r8188eu/include/rtl8188e_xmit.h

@@ -136,7 +136,6 @@ struct txrpt_ccx_88e {
 void rtl8188e_fill_fake_txdesc(struct adapter *padapter, u8 *pDesc,
 			       u32 BufferLen, u8 IsPsPoll, u8 IsBTQosNull);
 s32 rtl8188eu_init_xmit_priv(struct adapter *padapter);
-void rtl8188eu_free_xmit_priv(struct adapter *padapter);
 s32 rtl8188eu_hal_xmit(struct adapter *padapter, struct xmit_frame *frame);
 s32 rtl8188eu_mgnt_xmit(struct adapter *padapter, struct xmit_frame *frame);
 s32 rtl8188eu_xmit_buf_handler(struct adapter *padapter);