Update dependency handling in meson

[awvwgk]

Some code simplification in the build system to allow better caching of dependencies in superbuilds

[codecov]

Codecov Report

Merging #136 (f9499ee) into main (270d31b) will not change coverage.
The diff coverage is n/a.

❗ Current head f9499ee differs from pull request most recent head a63357c. Consider uploading reports for the commit a63357c to get more accurate results

@@           Coverage Diff           @@
##             main     #136   +/-   ##
=======================================
  Coverage   59.08%   59.08%           
=======================================
  Files          42       42           
  Lines        2977     2977           
  Branches     1016     1016           
=======================================
  Hits         1759     1759           
  Misses        640      640           
  Partials      578      578           

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