qcacmn: data-path changes for dynamic hw-mode config

This feature enables user to change HW mode dynamically
from DBS to DBS_SBS mode and vice-versa. Currently, HW
mode configuration is only possible through INI setting
requiring a subsequent reboot.

Relevant DP changes are:

1. Add API cdp_txrx_handle_pdev_status_change to pass
pdev 'up' or 'down' status to DP module
2. Add pdev-status check in dp_rx_process_invalid_peer
3. Add pdev-status check in dp_tx_comp_handler to free
buffer and release descriptor

Change-Id: I74b144abb1b0dc41a26a18ad28f872e6457e9653
CRs-fixed: 2490212

dp/inc/cdp_txrx_stats_struct.h

@@ -1717,6 +1717,8 @@ enum _ol_ath_param_t {
 	OL_ATH_PARAM_RCHWIDTH = 422,
 	/* Whether external ACS request is in progress */
 	OL_ATH_EXT_ACS_REQUEST_IN_PROGRESS = 423,
+	/* set/get hw mode */
+	OL_ATH_PARAM_HW_MODE  = 424,
 };
 #endif
 /* Bitmasks for stats that can block */