The UPF_RESOURCES flag was added to the serial layer to cater for
the idiosyncrasies of the PCMCIA layer, where the PCMCIA core code
handles the claiming of busy resources.

However, the PCMCIA core has progressed, and now does not claim busy
resources - IOW, it now behaves just like any other bus driver,
where resources are allocated non-busy and its up to the drivers to
mark their regions busy using request_region / request_mem_region.

The effect of this is that the UPF_RESOURCES hack in the serial
layer is now redundant, and can now be removed - 8250 devices
should now always use request_region / request_mem_region
unconditionally.

Signed-off-by: Russell King.