layers: Update CmdResolveImage validation

Added one VU check, changed a few others from errors to warnings as
they are not explictly prohibited by the spec.

Change-Id: I041f9188325136f541afa5017350c2960432f8f7
diff --git a/tests/layer_validation_tests.cpp b/tests/layer_validation_tests.cpp
index ef63ae6..b2dbb2d 100644
--- a/tests/layer_validation_tests.cpp
+++ b/tests/layer_validation_tests.cpp
@@ -16005,7 +16005,7 @@
     VkResult err;
     bool pass;
 
-    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_ERROR_BIT_EXT,
+    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_WARNING_BIT_EXT,
                                          "vkCmdResolveImage called with unmatched source and dest formats.");
 
     ASSERT_NO_FATAL_FAILURE(InitState());
@@ -16110,7 +16110,7 @@
     VkResult err;
     bool pass;
 
-    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_ERROR_BIT_EXT,
+    m_errorMonitor->SetDesiredFailureMsg(VK_DEBUG_REPORT_WARNING_BIT_EXT,
                                          "vkCmdResolveImage called with unmatched source and dest image types.");
 
     ASSERT_NO_FATAL_FAILURE(InitState());