RemoteLinux: Remove abstractremotelinuxrunsupport.{h,cpp}

There was only the now-unused FifoGatherer left, which could, if really
needed again, be re-instated near the actual worker that would need it.

Also, un-export LinuxDeviceDebugSupport and RemoteLinuxQmlProfilerSupport
which are not re-used, and conceptually not meant to be re-used, anymore.

Change-Id: I20b6eb2f4a85180b586ea8338cf74173e3b7b21c
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/remotelinux/remotelinuxdebugsupport.cpp

@@ -32,6 +32,7 @@ using namespace Debugger;
 using namespace ProjectExplorer;
 
 namespace RemoteLinux {
+namespace Internal {
 
 LinuxDeviceDebugSupport::LinuxDeviceDebugSupport(RunControl *runControl)
     : DebuggerRunTool(runControl)
@@ -67,4 +68,5 @@ void LinuxDeviceDebugSupport::start()
     DebuggerRunTool::start();
 }
 
+} // namespace Internal
 } // namespace RemoteLinux