layers: remove unnecessary log_msg
layers: remove unnecessary log_msg

Change-Id: I2ea237e46b028c0d2afa3a0f559eef42d8639a25

KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers