tty: serial: men_z135_uart.c: use mcb memory region size instead of hardcoded one

There is no need to hardcode the MEN_Z135_MEM_SIZE. The MCB subsystem
already knowns the size which is located in the chameleon table.
MCB parse the chameleon table to get the resources of each IP and provide
the mcb_request_mem function to get those resources.

Use mcb_request_mem to get the resources. This function also takes care of
the memory region naming allocated by the driver for each of the instances.

Signed-off-by: Andreas Werner <andy@wernerandy.de>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>