Cirrus CI: see if we can jam the raw Windows path into the UN*X environment.

If so, we can then do our own path construction from it, overriding the
garbage that we're getting from the system.

Author: guyharris

.cirrus.yml

@@ -84,7 +84,7 @@ windows_task:
     - curl -o AirPcap_Devpack.zip -L -s "https://support.riverbed.com/bin/support/download?sid=l3vk3eu649usgu3rj60uncjqqu"
     - 7z x .\AirPcap_Devpack.zip -oc:\projects\libpcap\Win32
   script:
-   - sh -c "echo $ORIGINAL_PATH; ./build_matrix.sh"
+   - sh -c "WINDOWS_PATH='%PATH%'"; export WINDOWS_PATH; env; ./build_matrix.sh"
 
 coverity_task:
   name: Coverity Scan