vulkan: Add temporary constant-data shader indexing tests.

vulkan: Add temporary constant-data shader indexing tests.

Drivers often have a path for taking shader temps that are initialized
with constant data and uploading them through the UBO path instead of
as shader immediates (particularly for dynamic indexing).  Add some
shader indexing tests that try to hit that path.

New tests:

dEQP-VK.glsl.indexing.tmp_array.*const_write*

Change-Id: I1072d796d8b4244c109eb5e639a291a0c49ca29e
Components: Vulkan