qcacld-3.0: Shutdown WLAN in system suspend prepare

This re-introduces the orignal patch which shutdowns WLAN in system
suspend prepare.

Orignal patch Id1f5172a7fc1792c83c8c1c20127de815f7e4980 is reverted by
Ic82db9dc0ca9d6686df99926335af27abc61cdb5 for deadlock issue.

However, deadlock between cnss_pm_notify and unregister_pm_notifier is
not caused by Id1f5172a7fc1792c83c8c1c20127de815f7e4980. So restore it
and add flag to enable/disable feature shutdown wlan in system suspend.

Deadlock issue is caused by "up_write(&cnss_pm_sem) is invoked before
down_write(&cnss_pm_sem) in function cnss_pm_notify". The issue can be
fixed by changes I533c373b85f554fbcceb562d9f56c6b88e5155bb and
I7768fdbeb1fa8cd6ef3b260eb0aafb231aeed324.

Change-Id: I25e4398a8d3b1a52cf7bc554af74d123ec797c6e
CRs-Fixed: 3287742

components/pmo/dispatcher/inc/wlan_pmo_common_cfg.h

@@ -340,13 +340,14 @@
  * <ini>
  * gSuspendMode - Suspend mode configuration
  * @Min: 0
- * @Max: 2
+ * @Max: 3
  * @Default: 2
  *
  * This ini is used to set suspend mode. Configurations are as follows:
  * 0 - Does not support suspend.
  * 1 - Legency suspend mode, PDEV suspend.
  * 2 - WOW suspend mode.
+ * 3 - Shutdown wlan while suspend.
  *
  * Related: None
  *
@@ -357,7 +358,7 @@
  * </ini>
  */
 #define CFG_PMO_SUSPEND_MODE CFG_INI_UINT("gSuspendMode", \
-					  0, 2, 2, \
+					  0, 3, 2, \
 					  CFG_VALUE_OR_DEFAULT, \
 					  "Suspend mode")
 

components/pmo/dispatcher/inc/wlan_pmo_common_public_struct.h

@@ -175,7 +175,7 @@ enum powersave_mode {
  * @PMO_SUSPEND_NONE: Does not support suspend
  * @PMO_SUSPEND_LEGENCY: Legency PDEV suspend mode
  * @PMO_SUSPEND_WOW: WoW suspend mode
- * @PMO_SUSPEND_SHUTDOWN: shutdown while suspend mode
+ * @PMO_SUSPEND_SHUTDOWN: Shutdown suspend mode. Shutdown while suspend
  */
 enum pmo_suspend_mode {
 	PMO_SUSPEND_NONE = 0,