solo5: don't call timers::ready before initializing devices

[ricarkol]

Some apps like tcp-perf do their work inside Service::ready instead of Service::start, so they expect a network stack at ready. Solo5 initialization currently calls Timers::init which calls Service::ready before initializing devices (in Solo5_manager::init). This change reorders that.

[jenkins-includeos]

Can one of the admins verify this patch with one of the following commands:

• "jenkins test please" for a one time test run
• "ok to test" to accept latest and future commits on this pull request for testing
• "add to whitelist" to add the author to the whitelist