test: log: log_process: Improve debugging on process exit failures

When the process fails to run and exit normally, the test prints an
error message that provides little information:

	process did not exit normally

Expand the error message to print the exit status to make debugging
easier.

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

test/log/log_process.cpp

@@ -86,7 +86,8 @@ protected:
 			dispatcher->processEvents();
 
 		if (exitStatus_ != Process::NormalExit) {
-			cerr << "process did not exit normally" << endl;
+			cerr << "process did not exit normally: " << exitStatus_
+			     << endl;
 			return TestFail;
 		}