Revert "Set vendor: true for boot control HAL"

This reverts commit f009da1bf51087cc33ae81101e3bf50df7683ecd.

Reason for revert: Breaking presubmit boot test on walleye

Change-Id: Ibeebb94b22cf81087b2ee60407a33e9d7e8a4d18
diff --git a/boot/1.0/default/Android.bp b/boot/1.0/default/Android.bp
index 397c56d..67dee08 100644
--- a/boot/1.0/default/Android.bp
+++ b/boot/1.0/default/Android.bp
@@ -2,7 +2,7 @@
     name: "android.hardware.boot@1.0-impl",
     defaults: ["hidl_defaults"],
     relative_install_path: "hw",
-    vendor: true,
+    vendor_available: true,
     recovery_available: true,
     srcs: ["BootControl.cpp"],