CI: remove travis details

Rename still used leftovers to "zuul" as that's now the CI using them.

Closes #7313

scripts/zuul/before_script.sh

@@ -145,9 +145,6 @@ if [ $TRAVIS_OS_NAME = linux -a "$WOLFSSL" ]; then
 fi
 
 # Install common libraries.
-# The library build directories are set to be cached by .travis.yml. If you are
-# changing a build directory name below (eg a version change) then you must
-# change it in .travis.yml `cache: directories:` as well.
 if [ $TRAVIS_OS_NAME = linux ]; then
 
   if [ "$MESALINK" = "yes" ]; then

scripts/zuul/script.sh

@@ -113,7 +113,7 @@ if [ "$T" = "tidy" ]; then
 fi
 
 if [ "$T" = "iconv" ]; then
-  source scripts/travis/iconv-env.sh
+  source scripts/zuul/iconv-env.sh
   ./configure --enable-debug --enable-werror $C
   make
   make examples