qcacmn: dfs : Fix compilation issue with dfs offload enable

Fix dfs_start_precac_timer() undefined symbol in dfs offload.

Change-Id: I05673b5827f448bed55133db809fd59b1a5fffd1
CRs-Fixed: 2280464

umac/dfs/core/src/dfs_zero_cac.h

@@ -138,8 +138,15 @@ void dfs_init_precac_list(struct wlan_dfs *dfs);
  * @dfs: Pointer to wlan_dfs structure.
  * @precac_chan: Start thr precac timer in this channel.
  */
+#if defined(WLAN_DFS_PARTIAL_OFFLOAD)
 void dfs_start_precac_timer(struct wlan_dfs *dfs,
-		uint8_t precac_chan);
+			    uint8_t precac_chan);
+#else
+static inline void dfs_start_precac_timer(struct wlan_dfs *dfs,
+					  uint8_t precac_chan)
+{
+}
+#endif
 
 /**
  * dfs_cancel_precac_timer() - Cancel the precac timer.