radv: fix wide lines with multisample enabled

radv: fix wide lines with multisample enabled

When set, EXPAND_LINE_WIDTH expands the line width by 1/cos(a),
where a is the minimum angle from horizontal or vertical. This
seems required by OpenGL line rasterization but not by Vulkan.

Similar to what AMDVLK and AMDGPU-PRO do for AA wide lines.

This fixes
dEQP-VK.rasterization.interpolation_multisample_*_bit.*lines_wide.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5698>