qcacmn: Enable configurable dfs_pri_multiplier

Enable configurable dfs_pri_multiplier. The ETSI typ2 type3 radar
detection ratio is lower than expected(>80%) while channel loading is
high(>30%). The host improvement for this are:
	1. Add configurable dfs_pri_multiplier, controlled by
	   DFS_PRI_MULTIPLIER. Default value 2, min 1, max 10.
	2. Lower adrastea ETSI type 2/3/4 radar filter rssi_threshold,
	   controlled by DFS_OVERRIDE_RF_THRESHOLD, dfs log shows that
	   QCS405 target report RSSI range [18, 45] while radar power
	   is 3 dbm. By using default rssi_threshold 24 will reject
	   many radar pulses, which leads to low detection ratio.
	3. Calculate deltapri for each searchpri based on dfs_pri_multiplier
	   in dfs_count_the_other_delay_elements(), check deltapri
	   between [1, dfs_pri_multiplier] * refpri and searchpri, if
	   the primargin is desired, mark it as matched pulse.
	4. Pick lowpri as refpri for the radar filter with
	   rf_ignore_pri_window equals to 0 while DFS_PRI_MULTIPLIER is
	   enabled. Observed original findref logic has some problems
	   which selects refpri is bigger than lowpri, which leads to
	   the lowpri pulses pri_match are set to 0, and in this case,
	   radar was not detected. Example for the issue, assume
	   rf->rf_pulseid 34 (ETSI type 2) has 7 pulses with pri:
	   1489, 2978, 2978, 2978, 1489, 2978, 1489 us in this case,
	   highscore is 4 (2978), scoreindex is 5, refpri is 2978, which
	   leads to: index 0, 4, 6 pulses with pri_match 0 in
	   dfs_count_the_other_delay_elements(). The fix is to select
	   lowpri as refpri(1489 in this case).

Change-Id: I1f3ca3298c9ab1f1e2651ad6b4a0a4810f83f8a1
CRs-Fixed: 2531811

umac/dfs/dispatcher/inc/wlan_dfs_ioctl.h

@@ -55,6 +55,7 @@
 
 #define DFS_INJECT_SEQUENCE 27
 #define DFS_ALLOW_HW_PULSES 28
+#define DFS_SET_PRI_MULTIPILER   29
 
 /*
  * Spectral IOCTLs use DFS_LAST_IOCTL as the base.