docker: Fix PATH for ccache

Before bcd7f06 we source /etc/profile
so the PATH included the right paths to ccache binaries. Now we need to
update $PATH explicitly from run script.

Keep the old /usr/lib around just so that in the future, ccache from 32
bit images will just work.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20171018073841.30062-1-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>

tests/docker/run

@@ -18,7 +18,7 @@ fi
 BASE="$(dirname $(readlink -e $0))"
 
 # Prepare the environment
-export PATH=/usr/lib/ccache:$PATH
+export PATH=/usr/lib/ccache:/usr/lib64/ccache:$PATH
 
 if test -n "$J"; then
     export MAKEFLAGS="$MAKEFLAGS -j$J"