AM/DM37x: DSS mux configuration for >Rev-B processor cards

To support higher resolution (e.g 720P@60), on OMAP36x (AM/DM37x)
DSS data bus has been muxed with sys_boot pins.

DSS[18-23] => DSS[0-5]
sys_boot[0,1 3-5] => DSS[18-23]

EVM revision >=RevB adopt this mux changes, which is going to ship outside.

Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>