staging: usbip: Fix bad fuction definitions in usbip

Fix bad function definitions in all files from drivers/staging/usbip directory
Signed-off-by: Pawel Lebioda <pawel.lebioda89@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/usbip/userspace/libsrc/usbip_common.c

@@ -237,7 +237,7 @@ int usbip_names_init(char *f)
 	return names_init(f);
 }
 
-void usbip_names_free()
+void usbip_names_free(void)
 {
 	names_free();
 }

drivers/staging/usbip/userspace/libsrc/vhci_driver.c

@@ -260,7 +260,7 @@ int usbip_vhci_driver_open(void)
 }
 
 
-void usbip_vhci_driver_close()
+void usbip_vhci_driver_close(void)
 {
 	if (!vhci_driver)
 		return;

drivers/staging/usbip/userspace/src/usbip_port.c

@@ -16,7 +16,7 @@
 #include "vhci_driver.h"
 #include "usbip_common.h"
 
-static int list_imported_devices()
+static int list_imported_devices(void)
 {
 	int i;
 	struct usbip_imported_device *idev;

drivers/staging/usbip/userspace/src/usbipd.c

@@ -458,7 +458,7 @@ static void set_signal(void)
 
 static const char *pid_file;
 
-static void write_pid_file()
+static void write_pid_file(void)
 {
 	if (pid_file) {
 		dbg("creating pid file %s", pid_file);
@@ -475,7 +475,7 @@ static void write_pid_file()
 	}
 }
 
-static void remove_pid_file()
+static void remove_pid_file(void)
 {
 	if (pid_file) {
 		dbg("removing pid file %s", pid_file);