Fixed major bug: drivers that accepted size arguments could wind

up with more than 80 characters (20x4) in their display, and thus
overwrite memory outside of the allocated 80 characterwframebuffer.

For example, using a 20x6 screen would do this.

All drivers now either ignore a missing framebuffer, or allocate it
themselves - the latter is prefered.

server/drivers/MtxOrb.c

@@ -361,12 +361,6 @@ MtxOrb_init (lcd_logical_driver * driver, char *args)
 	MtxOrb_cursorblink (DEFAULT_CURSORBLINK);
 	MtxOrb_contrast (contrast);
 
-	if (!driver->framebuf) {
-		syslog(LOG_ERR, "no frame buffer! exiting driver init...");
-		MtxOrb_close ();
-		return -1;
-	}
-
 	/*
 	 * Configure the display functions
 	 */