correctly mount tmpfs as /tmp in recovery

The syntax of init's mount command changed in April 2008 but
recovery's init.rc was never updated, so recovery's /tmp has been on
the root fs all this time.  Fix.

Also add /system/bin to the PATH in recovery, which is handy for
debugging.

Change-Id: I9e60d18803906bc75c263f12c8863cfd6a14147b
diff --git a/etc/init.rc b/etc/init.rc
index 8cff20e..39724d0 100644
--- a/etc/init.rc
+++ b/etc/init.rc
@@ -5,7 +5,7 @@
     start healthd
 
 on init
-    export PATH /sbin
+    export PATH /sbin:/system/bin
     export LD_LIBRARY_PATH .:/sbin
     export ANDROID_ROOT /system
     export ANDROID_DATA /data
@@ -16,7 +16,7 @@
     mkdir /system
     mkdir /data
     mkdir /cache
-    mount /tmp /tmp tmpfs
+    mount tmpfs tmpfs /tmp
 
     chown root shell /tmp
     chmod 0775 /tmp