tests: Fix some renderframework bugs
tests: Fix some renderframework bugs

Piers found a couple of typos in the device extension handling.

Change-Id: I0068f07bdbfca9715cac319feb56a3fc2b6402fb

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