Fix rocm warnings

Author: OliverRietmann

GPU/GPUTracking/DataTypes/GPUDataTypes.h

@@ -99,7 +99,7 @@ struct TPCZSLinkMapping;
 #include "utils/bitfield.h"
 
 template <template <class> class F>
-struct GPUTPCTrackSkeleton;
+class GPUTPCTrackSkeleton;
 class GPUTPCHitId;
 class GPUTPCGMMergedTrack;
 struct GPUTPCGMMergedTrackHit;

GPU/GPUTracking/SectorTracker/GPUTPCTrackParam.cxx

@@ -876,6 +876,8 @@ GPUd() int32_t GPUTPCTrackParamSkeleton<F>::GetPropagatedYZ(float bz, float x, f
   return 1;
 }
 
-template class GPUTPCTrackParamSkeleton<wrapper::value>;
-template class GPUTPCTrackParamSkeleton<wrapper::reference>;
-//template class GPUTPCTrackParamSkeleton<wrapper::const_reference>;
+namespace o2::gpu {
+  template class GPUTPCTrackParamSkeleton<wrapper::value>;
+  template class GPUTPCTrackParamSkeleton<wrapper::reference>;
+  //template class GPUTPCTrackParamSkeleton<wrapper::const_reference>;
+} // namespace o2::gpu

GPU/GPUTracking/SectorTracker/GPUTPCTracker.h

@@ -32,7 +32,7 @@ namespace o2::gpu
 struct GPUTPCClusterData;
 struct GPUParam;
 template <template <class> class F>
-struct GPUTPCTrackSkeleton;
+class GPUTPCTrackSkeleton;
 class GPUTPCRow;
 
 class GPUTPCTracker : public GPUProcessor