fbdev: fbmem: remove positive test on unsigned values

fb_image.dx, fb_image.dy and fbconf2bmap.framebuffer are __u32

Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/fbdev/core/fbmem.c

@@ -433,7 +433,7 @@ static void fb_do_show_logo(struct fb_info *info, struct fb_image *image,
 			image->dx += image->width + 8;
 		}
 	} else if (rotate == FB_ROTATE_UD) {
-		for (x = 0; x < num && image->dx >= 0; x++) {
+		for (x = 0; x < num; x++) {
 			info->fbops->fb_imageblit(info, image);
 			image->dx -= image->width + 8;
 		}
@@ -445,7 +445,7 @@ static void fb_do_show_logo(struct fb_info *info, struct fb_image *image,
 			image->dy += image->height + 8;
 		}
 	} else if (rotate == FB_ROTATE_CCW) {
-		for (x = 0; x < num && image->dy >= 0; x++) {
+		for (x = 0; x < num; x++) {
 			info->fbops->fb_imageblit(info, image);
 			image->dy -= image->height + 8;
 		}
@@ -1180,7 +1180,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
 			return -EFAULT;
 		if (con2fb.console < 1 || con2fb.console > MAX_NR_CONSOLES)
 			return -EINVAL;
-		if (con2fb.framebuffer < 0 || con2fb.framebuffer >= FB_MAX)
+		if (con2fb.framebuffer >= FB_MAX)
 			return -EINVAL;
 		if (!registered_fb[con2fb.framebuffer])
 			request_module("fb%d", con2fb.framebuffer);