Extend rasterization testing, modify verification

Extend rasterization testing, modify verification

dEQP-VK.rasterization.primitives.lines tests are extended to add tests
drawing vertical and horizontal lines.

Extend dEQP-VK.rasterization.primitives.lines and
dEQP-VK.rasterization.primitives_multisample_n_bit.lines to test at 258
resolution (a non power of two resolution).

The strict line verification coverage is modified to allow checking of
vertical and horizontal lines. Previously pixels in vertical or hori-
zontal lines were marked as partially covered and hence the test did
not detect whether the lines were rendered correctly or not.

Affects: dEQP-VK.rasterization.primitives*

Components: Vulkan

VK-GL-CTS Issue: 2062

Change-Id: Ifb76a44ba1ebdc97353bbd1a4b2552e415f2723d