[ROCm] Load ROCm if Torch is used as a dependency (#80469)
Includes LoadHIP.cmake if pytorch is used as a dependency for another project and ROCm is enabled. This removes the need to explicitly link against ROCm libraries in extension projects.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/80469
Approved by: https://github.com/pruthvistony, https://github.com/malfet
