drm/i915/vrr: require valid min/max vfreq for VRR

In the Linux kernel, the following vulnerability has been resolved: drm/i915/vrr: require valid min/max vfreq for VRR Ensure the EDID provided min/max vfreq are valid. Most scenarios are already covered (by coincidence) through the checks in intel_vrr_is_capable() and intel_vrr_is_in_range(), but be more explicit about it. At worst, a zero min_vfreq could lead to a division by zero in intel_vrr_compute_vmax(). Discovered using AI-assisted static analysis confirmed by Intel Product Security. (cherry picked from commit 1765cf59f517b02f3b0591fe5120930d08bddeb6)