media: ivtv: don't allow negative resolutions as module parameters

This driver takes "osd_xres" and "osd_yres" as module parameters and
caps the upper bounds but it doesn't cap the lower bounds.  Obviously
the admin is not going to enter negative resolutions but the possibility
makes static analysis more difficult.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/pci/ivtv/ivtvfb.c

@@ -48,8 +48,8 @@ static bool osd_laced;
 static int osd_depth;
 static int osd_upper;
 static int osd_left;
-static int osd_yres;
-static int osd_xres;
+static unsigned int osd_yres;
+static unsigned int osd_xres;
 
 module_param(ivtvfb_card_id, int, 0444);
 module_param_named(debug,ivtvfb_debug, int, 0644);
@@ -58,8 +58,8 @@ module_param(osd_laced, bool, 0444);
 module_param(osd_depth, int, 0444);
 module_param(osd_upper, int, 0444);
 module_param(osd_left, int, 0444);
-module_param(osd_yres, int, 0444);
-module_param(osd_xres, int, 0444);
+module_param(osd_yres, uint, 0444);
+module_param(osd_xres, uint, 0444);
 
 MODULE_PARM_DESC(ivtvfb_card_id,
 		 "Only use framebuffer of the specified ivtv card (0-31)\n"