agp: kill phys_to_gart() and gart_to_phys()

There seems to be no reason for these -- they're a 1:1 mapping on all
platforms.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/char/agp/sgi-agp.c b/drivers/char/agp/sgi-agp.c
index 0d47fa8..0d426ae 100644
--- a/drivers/char/agp/sgi-agp.c
+++ b/drivers/char/agp/sgi-agp.c
@@ -190,7 +190,7 @@
 	for (i = 0, j = pg_start; i < mem->page_count; i++, j++) {
 		table[j] =
 		    bridge->driver->mask_memory(bridge,
-						phys_to_gart(page_to_phys(mem->pages[i])),
+						page_to_phys(mem->pages[i]),
 						mem->type);
 	}