Revert "Cryptographic security for MAX_BOOT_LEVEL"

Revert submission 1660531-max-boot-level-crypto

Reason for revert: broken test com.android.tests.odsign.OnDeviceSigningHostTest#verifyArtUpgradeSignsFiles on aosp-master on aosp_cf_x86_64_phone-userdebug at 7261517

Reverted Changes:
Ia3b968afc:Set earlyBootEnded before apex starts
Ia69891291:Expose AID_KEYSTORE
I12530cd13:Cryptographic security for MAX_BOOT_LEVEL

Bug: 184635938
Change-Id: Ibcedeff47eb2e65307fa04093c5fd2297b76af71
Test: forrest run for the broken test
diff --git a/keystore2/src/keystore2_main.rs b/keystore2/src/keystore2_main.rs
index a6bbb2d..e745697 100644
--- a/keystore2/src/keystore2_main.rs
+++ b/keystore2/src/keystore2_main.rs
@@ -68,6 +68,13 @@
 
     ENFORCEMENTS.install_confirmation_token_receiver(confirmation_token_receiver);
 
+    info!("Starting boot level watcher.");
+    std::thread::spawn(|| {
+        keystore2::globals::ENFORCEMENTS
+            .watch_boot_level()
+            .unwrap_or_else(|e| error!("watch_boot_level failed: {}", e));
+    });
+
     entropy::register_feeder();
     shared_secret_negotiation::perform_shared_secret_negotiation();