Fix missing private clauses in 3D viscous GPU loops #5310

Job	Run time
Detect File Changes	10s
Lint Gate	56s
Github (ubuntu, mpi, debug, true)	2h 23m 5s
Github (macos, mpi, no-debug, false)	1h 5m 38s
Github (ubuntu, mpi, debug, false)	2h 3m 50s
Github (ubuntu, mpi, no-debug, true)	1h 35m 36s
Github (macos, mpi, debug, false)	51m 45s
Github (ubuntu, no-mpi, single, no-debug, false)	29m 1s
Github (ubuntu, mpi, no-debug, false)	2h 16m 55s
${{ matrix.cluster_name }} (${{ matrix.device }}${{ (((matrix.interface != 'none') && format('-{0}', matrix.interface)) \|\| '') }}${{ (((matrix.shard != '') && format(' [{0}]', matrix.shard)) \|\| '') }})	0s
Case Opt \| ${{ matrix.cluster_name }} (${{ matrix.device }}-${{ matrix.interface }})	0s
	10h 46m 56s

Provide feedback