Forward declare QtcProcess instead of #include

The QtcProcess is already forward declared in idevice.h.

In case of std::unique_ptr<MyClass> being a member
of a public class in a header file it's enough to
deinline constructor and destructor of a class
containing the member, and forward declare MyClass.

Amends f91a9cb891

Change-Id: Iacf272b62fed8827c0451c5d4c5c3429bb7106ef
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/android/androidsignaloperation.cpp

@@ -42,6 +42,8 @@ AndroidSignalOperation::AndroidSignalOperation()
     connect(m_timeout, &QTimer::timeout, this, &AndroidSignalOperation::handleTimeout);
 }
 
+AndroidSignalOperation::~AndroidSignalOperation() = default;
+
 void AndroidSignalOperation::adbFindRunAsFinished()
 {
     QTC_ASSERT(m_state == RunAs, return);