linux-postmarketos-exynos4: Add missing display panel support for GT-N710x

The current GT-N7100 and GT-N7105 ports only support the Samsung S6EVR02 display panel. However, some devices have a different panel based on the Magnachip EA8061 controller.

Add a driver for the Magnachip EA8061 panel. Users of those devices can now select between two kernel variants with different device trees (one for devices with the already supported S6EVR02 panel and one for the new EA8061 panel) during pmbootstrap init. Also enable both panels in the kernel config (S6EVR02 seems to have gotten disabled by accident).

I didn't write this driver myself. Just like the S6EVR02 driver, it has been ported from https://github.com/fourkbomb/linux to the latest mainline Linux version.

I've explained how to check the panel type of a device on the GT-N7100's wiki page: https://wiki.postmarketos.org/wiki/Samsung_Galaxy_Note_II_(samsung-t03g)#Display

There is a bug that the brightness doesn't get restored after disabling and re-enabling the display, but this issue also exists with the S6EVR02 panel according to the wiki.