Skip device validate if no need to run the test

This CL will allow user to keep building for device test eventhough
there's no device connect on the host if there's no test step need.

Bug: 261990108
Test: m atest ; atest-dev -b FrameworkStatsdTest
Test: m atest ; atest-dev FrameworkStatsdTest

Change-Id: I6c1b370feaa78a3c8ad173512a80efc6f9dced3c
1 file changed