video: omap2dss: fix LPAE warnings

If LPAE is enabled, dma_addr_t is 64 bit, so we have to
change a few type for everything in this driver to match
again.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Cc: linux-omap@vger.kernel.org
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>