Input: drivers/joystick - fix various sparse warnings

Fix various issues pointed by sparse:
 - module_param_array_named() takes unsigned int as number
   of parameters argument
 - shadowing of global variables is not healthy. I think there was
   once a bug in db9 caused by it.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/joystick/db9.c b/drivers/input/joystick/db9.c
index c27593b..86ad102 100644
--- a/drivers/input/joystick/db9.c
+++ b/drivers/input/joystick/db9.c
@@ -46,17 +46,17 @@
 
 struct db9_config {
 	int args[2];
-	int nargs;
+	unsigned int nargs;
 };
 
 #define DB9_MAX_PORTS		3
-static struct db9_config db9[DB9_MAX_PORTS] __initdata;
+static struct db9_config db9_cfg[DB9_MAX_PORTS] __initdata;
 
-module_param_array_named(dev, db9[0].args, int, &db9[0].nargs, 0);
+module_param_array_named(dev, db9_cfg[0].args, int, &db9_cfg[0].nargs, 0);
 MODULE_PARM_DESC(dev, "Describes first attached device (<parport#>,<type>)");
-module_param_array_named(dev2, db9[1].args, int, &db9[0].nargs, 0);
+module_param_array_named(dev2, db9_cfg[1].args, int, &db9_cfg[0].nargs, 0);
 MODULE_PARM_DESC(dev2, "Describes second attached device (<parport#>,<type>)");
-module_param_array_named(dev3, db9[2].args, int, &db9[2].nargs, 0);
+module_param_array_named(dev3, db9_cfg[2].args, int, &db9_cfg[2].nargs, 0);
 MODULE_PARM_DESC(dev3, "Describes third attached device (<parport#>,<type>)");
 
 #define DB9_ARG_PARPORT		0
@@ -680,17 +680,17 @@
 	int err = 0;
 
 	for (i = 0; i < DB9_MAX_PORTS; i++) {
-		if (db9[i].nargs == 0 || db9[i].args[DB9_ARG_PARPORT] < 0)
+		if (db9_cfg[i].nargs == 0 || db9_cfg[i].args[DB9_ARG_PARPORT] < 0)
 			continue;
 
-		if (db9[i].nargs < 2) {
+		if (db9_cfg[i].nargs < 2) {
 			printk(KERN_ERR "db9.c: Device type must be specified.\n");
 			err = -EINVAL;
 			break;
 		}
 
-		db9_base[i] = db9_probe(db9[i].args[DB9_ARG_PARPORT],
-					db9[i].args[DB9_ARG_MODE]);
+		db9_base[i] = db9_probe(db9_cfg[i].args[DB9_ARG_PARPORT],
+					db9_cfg[i].args[DB9_ARG_MODE]);
 		if (IS_ERR(db9_base[i])) {
 			err = PTR_ERR(db9_base[i]);
 			break;