Fix wrong line width when using Show Lines in Histogram scope

By not resetting the line width, other scopes were using the
wrong line thickness.

Contributed by RedMser.

Differential Revision: https://developer.blender.org/D12030

source/blender/editors/interface/interface_draw.c

@@ -411,6 +411,8 @@ static void histogram_draw_one(float r,
       immVertex2f(pos_attr, x2, y + (data[i] * h));
     }
     immEnd();
+  
+    GPU_line_width(1.0f);
   }
   else {
     /* under the curve */