[POWERPC] QE: Add support for Freescale QUICCEngine UART

Add support for UART serial ports using a Freescale QUICCEngine. Update
booting-without-of.txt to define new properties for a QE UART node.  Update
the MPC8323E-MDS device tree to add UCC5 as a UART.  Update the QE library
to support slow UCC devices and modules.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>