Add gsi_keys in first stage ramdisk

Currently GSI flashing and boot up procedure requires AVB
autentication disablement.This change adds GSI avb keys in ramdisk
and it will be matched against flashed GSI during first stage init.

Change-Id: I296868e3191e2f28d887d7eb7267090f193a4240
(cherry picked from commit 9a29440e427e4e7619b71c035815eaf72375fdc4)
diff --git a/device.mk b/device.mk
index 7e68db9..73d1eec 100644
--- a/device.mk
+++ b/device.mk
@@ -13,6 +13,9 @@
 endif
 $(call inherit-product, $(SRC_TARGET_DIR)/product/full_base_telephony.mk)
 
+# Installs gsi keys into ramdisk, to boot a GSI with verified boot.
+$(call inherit-product, $(SRC_TARGET_DIR)/product/gsi_keys.mk)
+
 # Enable updating of APEXes
 $(call inherit-product, $(SRC_TARGET_DIR)/product/updatable_apex.mk)
 
diff --git a/rootdir/etc/fstab.axolotl b/rootdir/etc/fstab.axolotl
index 4cecf40..bfcb641 100644
--- a/rootdir/etc/fstab.axolotl
+++ b/rootdir/etc/fstab.axolotl
@@ -1,6 +1,6 @@
 #<src>                          <mnt_point>     <type>  <mnt_flags and options>              <fs_mgr_flags>
 
-system                          /system         ext4    ro,barrier=1                         wait,slotselect,avb=vbmeta_system,logical,first_stage_mount
+system                          /system         ext4    ro,barrier=1                         wait,slotselect,avb=vbmeta_system,logical,first_stage_mount,avb_keys=/avb/q-gsi.avbpubkey:/avb/r-gsi.avbpubkey:/avb/s-gsi.avbpubkey
 system_ext                      /system_ext     ext4    ro,barrier=1                         wait,slotselect,avb=vbmeta_system,logical,first_stage_mount
 product                         /product        ext4    ro,barrier=1                         wait,slotselect,avb=vbmeta,logical,first_stage_mount
 odm                             /odm            ext4    ro,barrier=1                         wait,slotselect,avb=vbmeta_vendor,logical,first_stage_mount