.travis.yml: Disable IRC build status updates from forks

We want the travis build bot to post notifications on IRC only for the
master qemu repository and not the various forks/branches of
others. Currently there is no direct option to restrict the updates to
one repository. This is being worked upon by the developers and
tracked in https://github.com/travis-ci/travis-ci/issues/1094.

Until such time, we can use the workaround as posted in
ref. https://github.com/facebook/flow/pull/1822.

This basically creates an ecrypted string which decrypts to qemu IRC
channel only on "qemu/qemu" repo and not on the forks. This enables
the build bot to notify the IRC only for the main repo.
Signed-off-by: NPranith Kumar <bobby.prani@gmail.com>
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

.travis.yml

@@ -34,10 +34,13 @@ addons:
       - sparse
       - uuid-dev
 
+# The channel name "irc.oftc.net#qemu" is encrypted against qemu/qemu
+# to prevent IRC notifications from forks. This was created using:
+# $ travis encrypt -r "qemu/qemu" "irc.oftc.net#qemu"
 notifications:
   irc:
     channels:
-      - "irc.oftc.net#qemu"
+      - secure: "F7GDRgjuOo5IUyRLqSkmDL7kvdU4UcH3Lm/W2db2JnDHTGCqgEdaYEYKciyCLZ57vOTsTsOgesN8iUT7hNHBd1KWKjZe9KDTZWppWRYVwAwQMzVeSOsbbU4tRoJ6Pp+3qhH1Z0eGYR9ZgKYAoTumDFgSAYRp4IscKS8jkoedOqM="
     on_success: change
     on_failure: always
 env: