[BE] MapAllocator: report map error on Linux (#68545)
Summary:
Add `, strerror(errno), " (", errno, ")"` suffix to TORCH_CHECK messages that report failures from POSIX calls
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68545
Reviewed By: ngimel
Differential Revision: D32509300
Pulled By: malfet
fbshipit-source-id: 1d7792d07e3a1184d2d54d137e6a9105dbab7d4c
