usb: Remove __init from early_dbgp_init() prototype

Specifying these attributes in both the prototype and the function
definition is unnecessary and could cause confusion or bugs if they are
inconsistent.  As such, __init should only be specified at the function
definition.

Keith Owens suggested this as a janitorial task on LKML several years
ago:

  https://lkml.org/lkml/2006/1/14/305Signed-off-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/usb/ehci-dbgp.h

@@ -43,8 +43,7 @@ struct ehci_dbg_port {
 };
 
 #ifdef CONFIG_EARLY_PRINTK_DBGP
-#include <linux/init.h>
-extern int __init early_dbgp_init(char *s);
+extern int early_dbgp_init(char *s);
 extern struct console early_dbgp_console;
 #endif /* CONFIG_EARLY_PRINTK_DBGP */