frv: update comment in scatterlist to reflect new setup

#include <asm/types.h>

/*

 * Drivers must set either ->address or (preferred) ->page and ->offset

 * Drivers must set either ->address or (preferred) page and ->offset

 * to indicate where data must be transferred to/from.

 *

 * Using ->page is recommended since it handles highmem data as well as

 * Using page is recommended since it handles highmem data as well as

 * low mem. ->address is restricted to data which has a virtual mapping, and

 * it will go away in the future. Updating to ->page can be automated very

 * it will go away in the future. Updating to page can be automated very

 * easily -- something like

 *

 * sg->address = some_ptr;

 *

 * can be rewritten as

 *

 * sg->page = virt_to_page(some_ptr);

 * sg_set_page(virt_to_page(some_ptr));

 * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;

 *

 * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens