Revert "axolotl-shiftos: disable mainline modules"

This reverts commit d19747409d9a3c4e5e733a3493eac7c3281adbfe.

We have upgraded to mainline_t_2023_jan_t1005588, which restores
support for 4.9 kernels.

Change-Id: Iedba9c6e36e3fe7c877e5f5047babc7153a863b9
Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 8355cdc..1e4ffe2 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -9,11 +9,11 @@
 # Enable AVB 2.0
 BOARD_AVB_ENABLE := true
 
-#ifeq ($(WITH_GMS_MAINLINE),true)
-#    PRIVATE_KEY_PATH := vendor/shiftos/private/keys/mainline/avb-4096.pem
-#else
+ifeq ($(WITH_GMS_MAINLINE),true)
+    PRIVATE_KEY_PATH := vendor/shiftos/private/keys/mainline/avb-4096.pem
+else
     PRIVATE_KEY_PATH := vendor/shiftos/private/keys/stock/avb-4096.pem
-#endif
+endif
 
 # If private key does not exist, fallback to testkey
 ifeq ($(wildcard $(PRIVATE_KEY_PATH)),)