drivers/char/drm/ati_pcigart.c: fix printk warning

drivers/char/drm/ati_pcigart.c: In function 'drm_ati_pcigart_init':
drivers/char/drm/ati_pcigart.c:125: warning: format '%08X' expects type 'unsigned int', but argument 3 has type 'dma_addr_t'

Cc: Dave Airlie <airlied@linux.ie>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>