Handle VK_EXT_swapchain_colorspace in swapchain tests

VK_EXT_swapchain_colorspace adds new surface formats. Driver can enumerate
the formats regardless of whether VK_EXT_swapchain_colorspace was enabled,
but using them without enabling the extension is not allowed. Thus we have
two options:

1) Filter out non-core formats to stay within valid usage.

2) Enable VK_EXT_swapchain colorspace if advertised by the driver.

We opt for (2) as it provides basic coverage for the extension as a bonus.

Affects: dEQP-VK.wsi.*.swapchain.*
Components: Vulkan
VK-GL-CTS issue: 237

Change-Id: I5f905e5fb7ceaf83dacca57ef60d65487ff96d5d
(cherry picked from commit 703e4baead3c08331ee7604539d7a68a8b960c84)