drm: omapdrm: hdmi: Pass HDMI core version as integer to HDMI audio

The HDMI audio driver only needs to know which generation of HDMI
transmitter it deals with, not the detailed SoC model. Pass the version
number as an integer to prepare for removal of the OMAP SoC version from
the omapdrm driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>