Move unlink("/dev/.booting") until after filesystems are mounted.

Move the unlink out of init.c and into init.rc, so that the file
will be removed after all the filesystems with firmware are up.

Change-Id: I7442df2042cc2788d0301f00e3c2fba7d6e0e1c7
diff --git a/rootdir/init.rc b/rootdir/init.rc
index e2bc5b3..2c967cc 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -164,6 +164,10 @@
 on load_all_props_action
     load_all_props
 
+# Indicate to fw loaders that the relevant mounts are up.
+on firmware_mounts_complete
+    rm /dev/.booting
+
 # Mount filesystems and start core system services.
 on late-init
     trigger early-fs
@@ -179,6 +183,9 @@
     trigger early-boot
     trigger boot
 
+    # Remove a file to wake up anything waiting for firmware
+    trigger firmware_mounts_complete
+
 on post-fs
     # once everything is setup, no need to modify /
     mount rootfs rootfs / ro remount