qcacld-3.0: Reduce tx completion drain delay to 500 ms

Reduce tx completion drain delay to 500ms from 1sec to avoid
unwanted suspend delay.

Change-Id: I0fa49f8c754e5d6ad33bf0fec7b4e02154ef49bf
CRs-Fixed: 2047750

core/dp/txrx/ol_txrx.c

@@ -3630,7 +3630,7 @@ static QDF_STATUS ol_txrx_wait_for_pending_tx(int timeout)
 }
 
 #ifndef QCA_WIFI_3_0_EMU
-#define SUSPEND_DRAIN_WAIT 1000
+#define SUSPEND_DRAIN_WAIT 500
 #else
 #define SUSPEND_DRAIN_WAIT 3000
 #endif