Android: Merge output channels of AVD process

Otherwise, if the process produces a non-0 exit code, we get an error
message with only the stdout, which likely is empty.

Change-Id: I3b84f928cf786015aab499cdc2277d530d243841
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

src/plugins/android/androidavdmanager.cpp

@@ -297,6 +297,7 @@ bool AndroidAvdManager::startAvdAsync(const QString &avdName) const
         return false;
     }
     QProcess *avdProcess = new QProcess();
+    avdProcess->setReadChannelMode(QProcess::MergedChannels);
     QObject::connect(avdProcess,
                      static_cast<void (QProcess::*)(int)>(&QProcess::finished),
                      avdProcess,