qcacmn: Fix buffer overflow written in the dp_soc_interrupt_detach

Use sizeof instead of REG_BAND_UNKNOWN to fix buffer overflow written
in the dp_soc_interrupt_detach.

Change-Id: Iffad59346c487e34632f1c60b2c88e635f6e83a0
CRs-Fixed: 2822433

dp/wifi3.0/dp_main.c

@@ -2599,7 +2599,8 @@ static void dp_soc_interrupt_detach(struct cdp_soc_t *txrx_soc)
 	}
 
 	qdf_mem_set(&soc->mon_intr_id_lmac_map,
-		    REG_BAND_UNKNOWN * sizeof(int), DP_MON_INVALID_LMAC_ID);
+		    sizeof(soc->mon_intr_id_lmac_map),
+		    DP_MON_INVALID_LMAC_ID);
 }
 
 #define AVG_MAX_MPDUS_PER_TID 128