qcacld-3.0: define CONFIG_SHADOW_V2

Define CONFIG_SHADOW_V2 to continue using shadow
registers for QCA6290.

Change-Id: I342759910950489c53f69874a6e70f371ae04bca
CRs-Fixed: 2004391

Kbuild

@@ -1752,6 +1752,7 @@ CDEFINES += -DWLAN_FEATURE_NAN_DATAPATH
 endif
 
 ifeq ($(CONFIG_LITHIUM),y)
+CDEFINES += -DCONFIG_SHADOW_V2
 CDEFINES += -DQCA6290_HEADERS_DEF
 CDEFINES += -DQCA_WIFI_QCA6290
 CDEFINES += -DQCA_WIFI_QCA8074