Essential things for ChromeOS boards

This enables some important configs for ChromeOS boards, and adds a patch to fix coreboot framebuffer driver. Mainly so that the new debian-installer images I added for them will start being usable on x86 ones.

One thing to note is enabling FB_SIMPLE despite how it was disabled for #822575. Reading through pages linked there, I get the impression that enabling FB_SIMPLE while keeping X86_SYSFB (now SYSFB_SIMPLEFB) disabled doesn't trigger the bug. I also see a similar lockup on my x86 Chromebook if I enable SYSFB_SIMPLEFB and boot through alternative firmware which provides efifb from the same coreboot framebuffer.

Tested on an x86 Chromebook and an x86 AMD laptop. Will test on my arm64 Chromebook, currently building. My arm64 Chromebook boots fine as well, but doesn't do much there. Another firmware bug makes the coreboot framebuffer unusable and others except VPD isn't applicable for this model anyway.