msm7x30: Disable /boot mount & format in CWM

Change-Id: I7e5ff573810b9da2093a601a7985a3aa28c55851
msm7x30: Add releasetools extensions

Used to remove boot.img flashing from the updater script,
since boot partition is only writable through fastboot

Change-Id: If53cdf2439247874c71e2ee8af2bad797c78c6f4