SL-17274: PBR: Add kSpec debugging

indra/newview/app_settings/shaders/class3/deferred/softenLightF.glsl

@@ -51,6 +51,7 @@
 #define DEBUG_PBR_DOT_TV           0 // Output: grayscale dot(Tangent  ,Vertex2Camera)
 #define DEBUG_PBR_DOT_BV           0 // Output: graysacle dot(Bitangent,Vertex2Camera)
 #define DEBUG_PBR_FRESNEL          0 // Output: roughness dependent fresnel
+#define DEBUG_PBR_KSPEC            0 // Output: K spec
 #define DEBUG_PBR_IOR              0 // Output: grayscale IOR
 #define DEBUG_PBR_REFLECT0_BASE    0 // Output: black reflect0 default from ior
 #define DEBUG_PBR_REFLECT0_MIX     0 // Output: diffuse reflect0 calculated from ior