bug-14538: Remove validation error codes

https://cvs.khronos.org/bugzilla/show_bug.cgi?id=14538
diff --git a/icd/intel/gpu.c b/icd/intel/gpu.c
index a7a1a05..88b3cf2 100644
--- a/icd/intel/gpu.c
+++ b/icd/intel/gpu.c
@@ -402,14 +402,14 @@
 
     fd = gpu_open_render_node(gpu);
     if (fd < 0)
-        return VK_ERROR_UNKNOWN;
+        return VK_ERROR_INITIALIZATION_FAILED;
 
     gpu->winsys = intel_winsys_create_for_fd(gpu->handle.instance->icd, fd);
     if (!gpu->winsys) {
         intel_log(gpu, VK_DBG_REPORT_ERROR_BIT, 0,
                 VK_NULL_HANDLE, 0, 0, "failed to create GPU winsys");
         gpu_close_render_node(gpu);
-        return VK_ERROR_UNKNOWN;
+        return VK_ERROR_INITIALIZATION_FAILED;
     }
 
     return VK_SUCCESS;
@@ -469,7 +469,7 @@
    /* TODOVV: Move test to validation layer */
    if (*pCount > INTEL_GPU_ENGINE_COUNT) {
 //       return VK_ERROR_INVALID_VALUE;
-       return VK_ERROR_UNKNOWN;
+       return VK_ERROR_VALIDATION_FAILED;
    }
 
    for (engine = 0; engine < *pCount; engine++) {