Pixel clock property from DT is not used in OMAP DRM

[Tomas Novotny]

	Hi all,

I was trying to bring up parallel LCD on our custom board (similar to
BeagleBoard-xM) and I did it finally - but I needed to tweak hardcoded value
of 'Invert pixel clock'. Maybe I'm doing something wrong, but anyway:
	According to the display-timing.txt doc the 'pixelclk-active' DT
optional property is here. But this is not honored (through IPC bit of
DISPC_POL_FREQ register). The problem is that this property is hardcoded in 
copy_timings_drm_to_omap() in file drivers/gpu/drm/omapdrm/omap_connector.c
on that line:
timings->data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE;
	Other optional properties (ie. [hv]sync-active) are taken into the
account.
	I'm using 3.16-rc1 kernel from Tony's OMAP tree.
	Thanks and regards,

	Tomas