Enable tf-m-build-and-test concurrency

Enable many builds of tf-m-build-and-test to run concurrently, but limit
the number that it can run concurrently to avoid deadlocks.

Change-Id: I37c19d2317c77dea964abfdb7ccbb7d1d4b3f6ba
Signed-off-by: Dean Birch <dean.birch@arm.com>
1 file changed