Fix: EEVEE-Next: Incorect GGX reflection PDF

Fix #122291

source/blender/draw/engines/eevee_next/shaders/eevee_bxdf_microfacet_lib.glsl

@@ -208,7 +208,9 @@ BsdfEval bxdf_ggx_eval(vec3 N, vec3 L, vec3 V, float alpha, float eta, const boo
       float k = (1.0 - a2) * s2 / (s2 + a2 * square(Vt.z));
       eval.pdf = D / (2.0 * (k * Vt.z + t));
     }
-    eval.pdf = D * (t - Vt.z) / (2.0 * len_ai_sqr);
+    else {
+      eval.pdf = D * (t - Vt.z) / (2.0 * len_ai_sqr);
+    }
 
 #if 0 /* Should work without going into tangent space. But is currently wrong. */
     float sin_theta = sqrt(1.0 - square(NV));