Add mailbox driver from kernel 3.8.
Restore context in every case. If not, the status is not correctly handled by the mailbox and remoteproc
doesn't work anymore.
Reactivate logic to deactivate mailbox on suspend, since the mailbox context is now always restored on resume.
Increase the logging but mark them as comment.
Revert "Add mailbox driver from kernel 3.8."
This reverts commit 971f45eb17bddb0b97d417d584daf3280ecfeb39.

Since the mailbox 3.8 driver isn't working (easily) for the current remoteproc,
the old implementation is used.
Merge branch 'linux-jb-3.4_old_mailbox' into linux-jb-3.4
Fixed the 3.4 mailbox implementation to work with the 3.0 remoteproc implementation.