Fix bazel build after sleef update (#48614)
Summary:
In https://github.com/shibatch/sleef/pull/361 `src/libm/sleeflibm_header.h.org` was renamed to `src/libm/sleeflibm_header.h.org.in`
Updating bazel build rule for sleef accordingly
Pull Request resolved: https://github.com/pytorch/pytorch/pull/48614
Reviewed By: ezyang
Differential Revision: D25228160
Pulled By: malfet
fbshipit-source-id: dc0e56c2eb8990a19b5de14318e41ea9661c63f8
