apitrace: bump to version 7.0

Our current apitrace version can't detect the host-python version
correctly, so if both host-python and host-python3 where installed, it
will take the last one and it will fail with an "invalid syntax" error.
The latest apitrace version has this problem solved and it detects the
host-python version correctly.

Fixes:

  http://autobuild.buildroot.net/results/22a/22a73b4ba0adcc874ecc153917ae6edcfd4d37af/



Signed-off-by: Vicente Olivert Riera <Vincent.Riera@imgtec.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>