common: Drop floppy disk support

This seems pretty old now. It has not been converted to driver model and
is not used by any boards.

Drop it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/serial/serial_ns16550.c b/drivers/serial/serial_ns16550.c
index 5afe620..a1069f9 100644
--- a/drivers/serial/serial_ns16550.c
+++ b/drivers/serial/serial_ns16550.c
@@ -5,14 +5,9 @@
  */
 
 #include <common.h>
-#include <linux/compiler.h>
-
 #include <ns16550.h>
-#ifdef CONFIG_NS87308
-#include <ns87308.h>
-#endif
-
 #include <serial.h>
+#include <linux/compiler.h>
 
 #ifndef CONFIG_NS16550_MIN_FUNCTIONS