qcacld-3.0: Use OkcEnabled .ini flag to control firmware OKC

Turn off opportunistic key caching (OKC) in firmware based on
"OkcEnabled" parameter in WCNSS_qcom_cfg.ini.
It is enabled by default and can be turned off with value 0.
Remove FEATURE_WLAN_OKC compilation option because OKC is always
compiled in for cld3.0. Remove underlying empty routine
cb_notify_set_okc_feature_enabled().

CRs-Fixed: 1057181
Change-Id: I174e860abef0532d62517635fe56927d8c3c9fd3

Kbuild

@@ -79,9 +79,6 @@ ifeq ($(KERNEL_BUILD), 0)
 	#Flag to enable Legacy Fast Roaming3(LFR3)
 	CONFIG_QCACLD_WLAN_LFR3 := y
 
-	#JB kernel has PMKSA patches, hence enabling this flag
-	CONFIG_PRIMA_WLAN_OKC := y
-
 	# JB kernel has CPU enablement patches, so enable
 	ifeq ($(CONFIG_ROME_IF),pci)
 		CONFIG_PRIMA_WLAN_11AC_HIGH_TP := y
@@ -1176,10 +1173,6 @@ ifeq ($(CONFIG_QCACLD_WLAN_LFR2),y)
 CDEFINES += -DWLAN_FEATURE_HOST_ROAM
 endif
 
-ifeq ($(CONFIG_PRIMA_WLAN_OKC),y)
-CDEFINES += -DFEATURE_WLAN_OKC
-endif
-
 ifeq ($(BUILD_DIAG_VERSION),1)
 CDEFINES += -DFEATURE_WLAN_DIAG_SUPPORT
 CDEFINES += -DFEATURE_WLAN_DIAG_SUPPORT_CSR