pcmcia: Implement CLKRUN protocol disabling for Ricoh bridges

Currently, "disable_clkrun" yenta_socket module parameter is only
implemented for TI CardBus bridges.
Add also an implementation for Ricoh bridges that have the necessary
setting documented in publicly available datasheets.

Tested on a RL5C476II with a Sunrich C-160 CardBus NIC that doesn't work
correctly unless the CLKRUN protocol is disabled.

Let's also make it clear in its description that the "disable_clkrun"
module parameter only works on these two previously mentioned brands of
CardBus bridges.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>