Blackfin: uart: add multiple serial support

This brings CONFIG_SERIAL_MULTI support to the Blackfin on-chip UARTs.
Ends up adding only ~512bytes per additional UART.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

common/serial.c

@@ -172,6 +172,9 @@ void serial_initialize (void)
 #if defined(CONFIG_SYS_PSC6)
 	serial_register(&serial6_device);
 #endif
+#endif
+#if defined(CONFIG_SYS_BFIN_UART)
+	serial_register_bfin_uart();
 #endif
 	serial_assign (default_serial_console ()->name);
 }