travis: minor cleanup and ccache improvements

The changes here does not make ccache work much better, it still gets
tons of ccache misses in all project except QEMU v7 and Rpi3, but I
could see some improvements in the cache hit ratio, so it is probably
worth to keep them.

Signed-off-by: Joakim Bech <joakim.bech@linaro.org>
Acked-by: Jerome Forissier <jerome.forissier@linaro.org>
diff --git a/.travis.yml b/.travis.yml
index c319d28..1350982 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,6 @@
 
 dist: trusty
 sudo: required
-group: beta
 
 cache:
   directories:
@@ -42,6 +41,8 @@
   - $REPO_PROJ=rpi3
 
 before_script:
+  - export CCACHE_BASEDIR=$HOME/$REPO_PROJ
+  - export CCACHE_NOHASHDIR=1
   - mkdir -p $HOME/bin
   - cd $HOME/bin && wget https://storage.googleapis.com/git-repo-downloads/repo && chmod +x repo
   - export PATH=$HOME/bin:$PATH
@@ -61,7 +62,7 @@
                 branch=$TRAVIS_BRANCH
         fi
         echo "Getting ${REPO_PROJ}.xml from https://github.com/$slug using branch $branch"
-        cd $HOME/$REPO_PROJ && repo init -u https://github.com/$slug -b $branch -m ${REPO_PROJ}.xml </dev/null && repo sync -j2 --no-clone-bundle --no-tags --quiet
+        cd $HOME/$REPO_PROJ && repo init -u https://github.com/$slug -b $branch -m ${REPO_PROJ}.xml </dev/null && repo sync -j10 --no-clone-bundle --no-tags --quiet
   # Fetch a local copy of dtc+libfdt to avoid issues with a possibly outdated libfdt-dev
   - if [ $REPO_PROJ == "qemu_v8" ]; then cd $HOME/$REPO_PROJ/qemu && git submodule update --init dtc; fi
   # Dump the content of the manifest (for debug purpose)