layers: Removed obsolete CmdBlitImage check
layers: Removed obsolete CmdBlitImage check

Was enforcing VK_FILTER_NEAREST for integer formats but this is not
prohibited by the spec.

Change-Id: If9513bf9c660fc3c792e75004a257b3023539e3d

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