Use %pad format for values of the dma_addr_t type

The format change is to fix the following compilation issue:

../drivers/gpu/drm/omapdrm/omap_plane.c: In function 'omap_plane_pre_apply':
../drivers/gpu/drm/omapdrm/omap_plane.c:145:2: error: format '%x' expects argument of type 'unsigned int', but argument 5 has type 'dma_addr_t' [-Werror=format=]
  DBG("%d,%d %08x %08x", info->pos_x, info->pos_y,
  ^
../drivers/gpu/drm/omapdrm/omap_plane.c:145:2: error: format '%x' expects argument of type 'unsigned int', but argument 6 has type 'dma_addr_t' [-Werror=format=]
cc1: all warnings being treated as errors
../scripts/Makefile.build:273: recipe for target 'drivers/gpu/drm/omapdrm/omap_plane.o' failed

Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>