Remove LibIRC logic from cmake. (#31152)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31152
Per apaszke: I can't find any reasonable references to libIRC online, so
I decided to remove this.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Differential Revision: D19262582
Pulled By: ezyang
fbshipit-source-id: a1d47462427a3e0ca469062321d608e0badf8548
