qcacmn: Remove dp_tx_pdev_detach API

dp_tx_pdev_detach API takes care of flushing
tx descriptors and multicast enhancement mem
cleanup

dp_pdev_deinit takes care of cleaning up the
above actions and dp_tx_pdev_detach is simply
a redundant piece of code

Hence remove dp_tx_pdev_detach API and call
dp_tx_desc_flush directly from dp_pdev_deinit

CRs-Fixed: 2769303
Change-Id: Ic798793e81eefc7dc905ca7552fdca13e9fddd8c

dp/wifi3.0/dp_tx.h

@@ -188,8 +188,6 @@ QDF_STATUS dp_tx_tso_cmn_desc_pool_alloc(struct dp_soc *soc,
 QDF_STATUS dp_tx_tso_cmn_desc_pool_init(struct dp_soc *soc,
 					uint8_t num_pool,
 					uint16_t num_desc);
-QDF_STATUS dp_tx_pdev_detach(struct dp_pdev *pdev);
-QDF_STATUS dp_tx_pdev_attach(struct dp_pdev *pdev);
 
 void dp_tx_tso_cmn_desc_pool_deinit(struct dp_soc *soc, uint8_t num_pool);
 void dp_tx_tso_cmn_desc_pool_free(struct dp_soc *soc, uint8_t num_pool);