Use `ANTENNAGATEAREA` from LEF views of cells.

[kareefardi]

At the moment, magic doesn't use ANTENNAGATEAREA of pins in the LEF views of cells that it reads. It can potentially use it to generate ANTENNAGATEAREA for pins while writing a LEF view.

Here is a test case for this: test-case.tar.gz This requires env variable PDK_ROOT set and sky130A inside the PDK_ROOT

[RTimothyEdwards]

This cannot be done without substantial revision of magic's code. The antenna gate and diffusion areas are measured during "lef write" by walking each net and measuring the areas directly. The proper solution is to make sure that you only write LEF from a layout containing no abstract views.