Remove adding /odm from GSI makefile

The odm/ is default created under the root directory.
We don't need adding /odm mount pointer now in GSI.

Bug: 77297861
Test: build aosp_arm64_ab-userdebug and boot on a Pixel 2 device.
Change-Id: Ied48439f366acc33595b958b75c2f30d8f6ad57e
diff --git a/target/board/treble_common.mk b/target/board/treble_common.mk
index 26a2655..bf07e28 100644
--- a/target/board/treble_common.mk
+++ b/target/board/treble_common.mk
@@ -47,11 +47,6 @@
 # Audio
 USE_XML_AUDIO_POLICY_CONF := 1
 
-# b/64700195: add minimum support for odm.img
-# Currently odm.img can only be built by `make custom_images`.
-# Adding /odm mount point under root directory.
-BOARD_ROOT_EXTRA_FOLDERS += odm
-
 # Android Verified Boot (AVB):
 #   Builds a special vbmeta.img that disables AVB verification.
 #   Otherwise, AVB will prevent the device from booting the generic system.img.