drm/exynos: add phy settings for RB resolutions

drm/exynos: add phy settings for RB resolutions

This patch adds support for the below mentioned
pixel clocks in Exynos5250.
Without them, following display modes won¡¯t
be supported:

71 MHz 	- 1280x800@60Hz RB
73.25 MHz 	- 800x600@120Hz RB
88.75 MHz 	- 1440x900@60Hz RB
115.5 MHz 	- 1024x768@120Hz RB
119 MHz 	- 1680x1050@60Hz RB

Signed-off-by: Shirish S <s.shirish@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>