pata: remove samsung_cf driver

This device was only used by the smdk6410 board file that is now
gone, so the driver can be removed as well.

Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>