Move adb_keys to product partition

/adb_keys will be moved to /product/etc/security as it's a
product-specific file. To prevent regression, /adb_keys will be a
symlink to the new location.

Bug: 353430323
Test: boot and connect adb with ADB_VENDOR_KEYS
Change-Id: Ie5f50b590f4f2fce8630c87be54a175ff5cedae3
diff --git a/private/file_contexts b/private/file_contexts
index d49be64..48f00ed 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -24,7 +24,7 @@
 /                   u:object_r:rootfs:s0
 
 # Data files
-/adb_keys           u:object_r:adb_keys_file:s0
+/adb_keys           u:object_r:system_file:s0
 /build\.prop        u:object_r:rootfs:s0
 /default\.prop      u:object_r:rootfs:s0
 /fstab\..*          u:object_r:rootfs:s0
@@ -507,6 +507,8 @@
 
 /(product|system/product)/lib(64)?(/.*)?                         u:object_r:system_lib_file:s0
 
+/(product|system/product)/etc/security/adb_keys                 u:object_r:adb_keys_file:s0
+
 #############################
 # SystemExt files
 #