test: Store path to the test executable in Test class

Store the path to the test executable, found in argv[0], in the Test
instance. This can be useful for tests that need to fork processes.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

test/ipc/unixsocket.cpp

@@ -501,5 +501,7 @@ int main(int argc, char **argv)
 		return slave.run(ipcfd);
 	}
 
-	return UnixSocketTest().execute();
+	UnixSocketTest test;
+	test.setArgs(argc, argv);
+	return test.execute();
 }