radv: add support for VK_EXT_depth_range_unrestricted

radv: add support for VK_EXT_depth_range_unrestricted

This extension removes the restrictions on minDepth/maxDepth,
minDepthBounds/maxDepthBounds and VkClearDepthStencilValue::depth.

The following CTS tests now pass:

dEQP-VK.glsl.builtin_var.fragdepth.line_list_d32_sfloat_large_depth
dEQP-VK.glsl.builtin_var.fragdepth.point_list_d32_sfloat_large_depth
dEQP-VK.glsl.builtin_var.fragdepth.triangle_list_d32_sfloat_large_depth
dEQP-VK.draw.inverted_depth_ranges.nodepthclamp_depth_range_unrestricted
dEQP-VK.draw.inverted_depth_ranges.depthclamp_depth_range_unrestricted

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>