Fix asserts and check for base image format support in image.mutable tests

Fix asserts and check for base image format support in image.mutable tests

This adds a check if base image can be created given the format.

It is required for implementations supporting VK_KHR_maintenance2 or 1.1:
if these are supported, the exisiting VkImageView format support does not
cover base image format support.

Additionally, fix malformed asserts and missign case switches in this test.

Components: Vulkan

Affects: dEQP-VK.image.mutable

VK-GL-CTS Issue: 1295, 1294

Change-Id: I010a8823e2f7fa53a845366e489f071dbdc2f7f2