pcmcia: remove RPX board stuff

The RPX board is not supported by the kernel because CONFIG_RPXCLASSIC and
CONFIG_RPXLITE symbols and not defined anywhere. Clean-up the m8xx_pcmcia
driver a little bit.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: linux-pcmcia@lists.infradead.org
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>