kunit: tool: drop unused KernelDirectoryPath var

Commit be886ba90cce ("kunit: run kunit_tool from any directory")
introduced this variable, but it was unused even in that commit.

Since it's still unused now and callers can instead use
get_kernel_root_path(), delete this var.

Signed-off-by: Daniel Latypov <[e-mail]>
Reviewed-by: David Gow <[e-mail]>
Reviewed-by: Brendan Higgins <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/kunit/kunit.py

···
 	pass
 
 
-KernelDirectoryPath = sys.argv[0].split('tools/testing/kunit/')[0]
-
 def get_kernel_root_path() -> str:
 	path = sys.argv[0] if not __file__ else __file__
 	parts = os.path.realpath(path).split('tools/testing/kunit')