This change allows pyunit tests to be run on specific directories
instead of the default `pyunit` directory.
You can pass in the directory as follows. I have built gem5.opt for
RISCV however it should work the same with other builds
```
./build/RISCV/gem5.opt tests/run_pyunit.py --directory tests/pyunit/gem5/
```
The default path works as it is currently
```
./build/RISCV/gem5.opt tests/run_pyunit.py
```
Change-Id: Id9cc17498fa01b489de0bc96a9c80fc6b639a43f
Signed-off-by: Suraj Shirvankar <surajshirvankar@gmail.com>
44aaebc49a