Allow init to mount on /bionic in recovery mode

The mount points under /bionic are rootfs in recovery mode. Init should
be able to bind-mount the bootstrap Bionic to the mount points.

Bug: 120266448
Test: adb reboot recovery; phone enters into the recovery mode
Change-Id: I57aed268eac08a5fb3609750bf10cd8d6e97347a
diff --git a/public/init.te b/public/init.te
index 7a8bc58..a089c8c 100644
--- a/public/init.te
+++ b/public/init.te
@@ -87,8 +87,14 @@
 # Mount tmpfs on /apex
 allow init apex_mnt_dir:dir mounton;
 
+# Mount Bionic libraries and dynamic linkers
 allow init system_lib_file:file mounton;
 allow init system_linker_exec:file mounton;
+# The mount points under /bionic are rootfs in recovery mode. Init should
+# be able to bind-mount the bootstrap Bionic to the mount points.
+recovery_only(`
+  allow init rootfs:file mounton;
+')
 
 # Create and remove symlinks in /.
 allow init rootfs:lnk_file { create unlink };