Fix C2 Ambiguous namespace (#89534)
Summary: cuda:: is a ambiguous namespace. Make it explicit c10::cuda
Differential Revision: D41469007
/caffe2/caffe2/core/context_gpu.cu(564): error: "caffe2::cuda" is ambiguous/caffe2/caffe2/core/context_gpu.cu(564): error: expected a ";"/caffe2/caffe2/core/context_gpu.cu(568): warning #12-D: parsing restarts here after previous syntax error
Remark: The warnings can be suppressed with "-diag-suppress <warning-number>"/caffe2/caffe2/core/context_gpu.cu(569): error: "caffe2::cuda" is ambiguous/caffe2/caffe2/core/context_gpu.cu(628): error: "caffe2::cuda" is ambiguous
4 errors detected in the compilation of "/caffe2/caffe2/core/context_gpu.cu".
Pull Request resolved: https://github.com/pytorch/pytorch/pull/89534
Approved by: https://github.com/malfet
