Reinstate RTEMS 4.11 build

[jphickey]

Describe the bug
The RTEMS 4.11 build fails because it does not implement pthread_setname_np.

To Reproduce
Build with RTEMS 4.11, error on call to pthread_setname_np

Expected behavior
Success

System observed on:
Debian with RTEMS 4.11 toolchain

Additional context
Although this OS is "obsolete" -- it still provides valuable feedback to the code quality, in particular because int and long map to different C fundamental types, and this exposes a number of coding/conversion errors. Therefore it still serves as a good litmus test for how the code is likely perform on older architectures.

Reporter Info
Joseph Hickey, Vantage Systems, Inc.