[console] Move putchar() and getchar() declarations to stdio.h

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/core/vsprintf.c

@@ -21,7 +21,6 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <stddef.h>
 #include <stdarg.h>
 #include <stdio.h>
-#include <ipxe/console.h>
 #include <errno.h>
 #include <ipxe/vsprintf.h>