Fix usb debug dongle support

- move enable_usbdebug() declaration to usbdebug.h
- reinitialize debug driver in ramstage, as copying the data
  structure from romstage doesn't work right now. This way of copying
  data from romstage to ramstage is really board/cpu specific, and is
  likely to break often. So don't do it.

Change-Id: I394678ded6679c1803e29eb691b926182bdcab68
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-on: http://review.coreboot.org/355
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/include/usbdebug.h

@@ -32,6 +32,8 @@ struct ehci_debug_info {
         u32 endpoint_in;
 };
 
+#ifndef __ROMCC__
+void enable_usbdebug(unsigned int port);
 int dbgp_bulk_write_x(struct ehci_debug_info *dbg_info, const char *bytes, int size);
 int dbgp_bulk_read_x(struct ehci_debug_info *dbg_info, void *data, int size);
 void set_ehci_base(unsigned ehci_base);
@@ -40,5 +42,6 @@ unsigned get_ehci_debug(void);
 void set_debug_port(unsigned port);
 int early_usbdebug_init(void);
 void usbdebug_tx_byte(unsigned char data);
-
+int usbdebug_init(unsigned ehci_bar, unsigned offset, struct ehci_debug_info *info);
+#endif
 #endif