compiler: Add a system value and varying for ViewIndex

Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>

src/compiler/shader_enums.c

@@ -162,6 +162,7 @@ gl_varying_slot_name(gl_varying_slot slot)
       ENUM(VARYING_SLOT_TESS_LEVEL_INNER),
       ENUM(VARYING_SLOT_BOUNDING_BOX0),
       ENUM(VARYING_SLOT_BOUNDING_BOX1),
+      ENUM(VARYING_SLOT_VIEW_INDEX),
       ENUM(VARYING_SLOT_VAR0),
       ENUM(VARYING_SLOT_VAR1),
       ENUM(VARYING_SLOT_VAR2),
@@ -232,6 +233,7 @@ gl_system_value_name(gl_system_value sysval)
      ENUM(SYSTEM_VALUE_GLOBAL_INVOCATION_ID),
      ENUM(SYSTEM_VALUE_WORK_GROUP_ID),
      ENUM(SYSTEM_VALUE_NUM_WORK_GROUPS),
+     ENUM(SYSTEM_VALUE_VIEW_INDEX),
      ENUM(SYSTEM_VALUE_VERTEX_CNT),
    };
    STATIC_ASSERT(ARRAY_SIZE(names) == SYSTEM_VALUE_MAX);