ConsoleProcess: Uniform the common interface of QtcProcess

This is a preliminary step before merging ConsoleProcess
into QtcProcess.

Don't return bool from start(), all callers ignored it.
Rename stop() to stopProcess().

Change-Id: I2fda1337e6f490685669fbd7ad6987a97866fdbe
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/terminal.cpp

@@ -224,7 +224,7 @@ void TerminalRunner::start()
 
 void TerminalRunner::stop()
 {
-    m_stubProc.stop();
+    m_stubProc.stopProcess();
     reportStopped();
 }