OMAP4: DSS2: HDMI: Rename the functions in HDMI IP library

Functions that are included in HDMI IP driver is renamed to have
IP specific names so that it will not conflict with similar functions
from other IP.

Signed-off-by: Mythri P K <mythripk@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>