Merge branch 'scygan_pipelineVertexInput_64bit_locations' into 'master'

pipeline/vktPipelineVertexInputTests: fixed attribute location for double formats

The tests uses 3- and 4-element double (fp64) vertex attributes, but does not provide enough location space for these.

According to spec:
```
 Input attributes which have three- or four-component 64-bit formats will consume two consecutive locations.
```

See merge request !275

diff --cc external/vulkancts/modules/vulkan/pipeline/vktPipelineVertexInputTests.cpp
Simple merge