OMAP: DSS2: OMAPFB: Remove redundant rotate range check

Unsigned rotate can never be less than zero. Found by Coverity.
Signed-off-by: NJani Nikula <ext-jani.1.nikula@nokia.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@nokia.com>

drivers/video/omap2/omapfb/omapfb-main.c

@@ -683,7 +683,7 @@ int check_fb_var(struct fb_info *fbi, struct fb_var_screeninfo *var)
 		}
 	}
 
-	if (var->rotate < 0 || var->rotate > 3)
+	if (var->rotate > 3)
 		return -EINVAL;
 
 	if (check_fb_res_bounds(var))