Update .travis.yml

remove LEAmDNS which failed to compile but we do not use it

Author: Luc

.travis.yml

@@ -27,6 +27,7 @@ before_script:
   - echo 'build.flash_mode=dio' >> platform.txt
   - echo 'build.f_cpu=160000000L' >> platform.txt
   - sed -i "s/generic.build.f_cpu=80000000L/generic.build.f_cpu=160000000L/g" ./boards.txt
+  - rm -fr "./libraries/ESP8266mDNS/src/LEA*.*
   - cd $HOME/arduino_ide/hardware
   - mkdir esp32
   - cd esp32