gallium/util: Add const to u_range_intersect

This doesn't modify the range, so it can accept a const pointer.

Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>

src/gallium/auxiliary/util/u_range.h

@@ -67,7 +67,8 @@ util_range_add(struct util_range *range, unsigned start, unsigned end)
 }
 
 static inline boolean
-util_ranges_intersect(struct util_range *range, unsigned start, unsigned end)
+util_ranges_intersect(const struct util_range *range,
+                      unsigned start, unsigned end)
 {
    return MAX2(start, range->start) < MIN2(end, range->end);
 }