qcacld-3.0: Add a feature flag WLAN_POWER_DEBUG for power stats

Power stats is moved from debugfs to sysfs, and hence add the feature
flag WLAN_POWER_DEBUG such that this feature can be compiled out for
low memory foot print drivers.

Change-Id: Ic395f393580fcd59faa4e4676f67a39ff37bdd1a
CRs-Fixed: 2665089
diff --git a/Kbuild b/Kbuild
index a5a59cc..f991e56 100644
--- a/Kbuild
+++ b/Kbuild
@@ -2445,7 +2445,7 @@
 
 cppflags-$(CONFIG_FEATURE_ROAM_DEBUG) += -DFEATURE_ROAM_DEBUG
 
-cppflags-$(CONFIG_WLAN_POWER_DEBUGFS) += -DWLAN_POWER_DEBUGFS
+cppflags-$(CONFIG_WLAN_POWER_DEBUG) += -DWLAN_POWER_DEBUG
 
 cppflags-$(CONFIG_WLAN_MWS_INFO_DEBUGFS) += -DWLAN_MWS_INFO_DEBUGFS