Make the FrameBufferWriter and logger in to a separate crate so it can be reused by a kernel for quick start?

[duggaraju]

Right now the bootloader-x86_64-common crate has std dependencies. and doesn't compile with no_std flag. If that can be made to work with no_std or move the framebuffer logic to a separate crate it would be usable by kernel code and helps with quick start of a kernel that can log messages.

[zjijz]

bootloader-x86_64-common can (now) be compiled with no_std (

bootloader/common/src/lib.rs

Line 1 in 7c8e2ca

#![no_std]

) and it did work in my custom kernel.