[fb] Create fb driver

Create a new framebuffer driver. Also hackily passing frame buffer size
in the list of init handles to all processes and mapping the framebuffer
into all processes. Changed bootloader passing frame buffer as a module
to its own struct.

src/kernel/scheduler.h

@@ -45,7 +45,8 @@ public:
 	/// \arg virt  Virtual address of the loaded program image
 	/// \arg size  Size of the program image, in bytes
 	/// \arg entry Virtual address of the program entrypoint
-	void load_process(uintptr_t phys, uintptr_t virt, size_t size, uintptr_t entry);
+	/// \returns   The main thread of the loaded process
+	thread * load_process(uintptr_t phys, uintptr_t virt, size_t size, uintptr_t entry);
 
 	/// Create a new kernel task
 	/// \arg proc     Function to run as a kernel task