qcacmn: conditionally compile dp_mon_register_intr_ops

Currently dp_mon_register_intr_ops is defined conditionally
using DISABLE_MON_CONFIG macro but function call is independent of
DISABLE_MON_CONFIG which may cause compilation issue when
DISABLE_MON_CONFIG is disabled.

Fix is to add void function definition when DISABLE_MON_CONFIG
is disabled.

Change-Id: I5f0bafa1aa3560a5828500a687b8b11178ab945b
CRs-Fixed: 3084193

dp/wifi3.0/monitor/dp_mon.h

@@ -180,6 +180,9 @@ void dp_mon_ops_register(struct dp_soc *soc);
 
 #ifndef DISABLE_MON_CONFIG
 void dp_mon_register_intr_ops(struct dp_soc *soc);
+#else
+static inline void dp_mon_register_intr_ops(struct dp_soc *soc)
+{}
 #endif
 
 /*