[ARM] Support pcmcia slot on sharp sl-5500

This adds support for pcmcia slot on sharp zaurus sl-5500.
pxa2xx_sharpsl.c thus becomes quite miss-named, but I guess that
is not worth fixing?

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>