[PATCH] drivers: ld9040 amoled driver support

[leedonghwa]

Hi, Andrew and Paul

A month had elapsed since my patch was posted in mainline, but, 
there is no review about it. So I make a request again to review
it.
As I explained before, ld9040 driver is very simple driver to 
control amoled lcd panel. And it is very similar with s6e63m0 
amoled driver, the difference is nothing but each specific 
registers value. 

Please review it.

Thank you,
Donghwa Lee