Revert python3-crcmod install

Python3 on Travis is old (3.5) so crcmod is installed by pip anyway.

Revert python3-crcmod install
130aec16 · Jean-Michel Picod · 3eef0ec8 · 130aec16
Commit 130aec16 authored Feb 6, 2020 by Jean-Michel Picod
--- a/.travis.yml
+++ b/.travis.yml
@@ -26,7 +26,6 @@ addons:
      - "python3-pip"
      - "python3-setuptools"
      - "python3-wheel"
-      - "python3-crcmod"

 cache:
  - rust