Split framebuffer functions into library

src/kernel/include/terminal.h

@@ -1,5 +1,6 @@
 #pragma once
-#include <framebuffer.h>
+#include <mittos/graphics.h>
+#include <multiboot.h>
 
 #define VGA_COLS 80
 #define VGA_ROWS 24
@@ -21,6 +22,7 @@ void vga_movecursor(unsigned int cursor);
 void vga_flush(struct vga_cell *buffer);
 
 // drivers/terminal/fbterm.c
-void fbterm_init(gfx_context *ctx);
+extern gfx_context kernel_fb;
+void fbterm_init(struct fbinfo *fbinfo);
 void fbterm_movecursor(unsigned int cursor);
 void fbterm_flush(struct vga_cell *buffer);