Revert "nvc0: fix line width on GM20x+"

This reverts commit a0e57432.

It's unclear what caused the test to fail back then. Now it's seems to be reversed. I tested with a close enough piglit and mesa branch and wasn't able to reproduce the same test result I've got in some older piglit runs.

Fixes:

dEQP-GLES2.functional.rasterization.primitives.lines_wide
dEQP-GLES2.functional.rasterization.primitives.line_strip_wide
dEQP-GLES2.functional.rasterization.primitives.line_loop_wide
dEQP-GLES2.functional.rasterization.limits.points
dEQP-GLES2.functional.clipping.line.wide_line_z_clip
dEQP-GLES2.functional.clipping.line.wide_line_z_clip_viewport_center
dEQP-GLES2.functional.clipping.line.wide_line_z_clip_viewport_corner
dEQP-GLES2.functional.clipping.line.wide_line_clip
dEQP-GLES2.functional.clipping.line.wide_line_clip_viewport_center
dEQP-GLES2.functional.clipping.line.wide_line_clip_viewport_corner
dEQP-GLES2.functional.clipping.line.wide_line_attrib_clip
dEQP-GLES2.functional.polygon_offset.default_result_depth_clamp
dEQP-GLES2.functional.polygon_offset.default_factor_1_slope
dEQP-GLES2.functional.polygon_offset.fixed16_result_depth_clamp
dEQP-GLES2.functional.polygon_offset.fixed16_factor_1_slope