tests: Fix image tiling enum to work on nvidia.

Also add robustness fixes so that a failed image creation
does not crash the process.

Change-Id: I14fd56c3968c1bd58c3b89bb2f805da7231df7af
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index b2ebab4..99ce40a 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -1130,7 +1130,7 @@
 TEST_F(VkLayerTest, InvalidUsageBits)
 {
     TEST_DESCRIPTION(
-        "Specify wrong usage for image then create conflictiong view of image "
+        "Specify wrong usage for image then create conflicting view of image "
         "Initialize buffer with wrong usage then perform copy expecting errors "
         "from both the image and the buffer (2 calls)");
     m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_ERROR_BIT_EXT,
@@ -1140,7 +1140,8 @@
     VkImageObj image(m_device);
     // Initialize image with USAGE_INPUT_ATTACHMENT
     image.init(128, 128, VK_FORMAT_D32_SFLOAT_S8_UINT,
-               VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_TILING_LINEAR, 0);
+               VK_IMAGE_USAGE_INPUT_ATTACHMENT_BIT, VK_IMAGE_TILING_OPTIMAL, 0);
+    ASSERT_TRUE(image.initialized());
 
     VkImageView dsv;
     VkImageViewCreateInfo dsvci = {};