Kill more unused THCUNN operators. (#26971)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26971
I believe this is currently exhaustive of the unused operators in THCUNN:
LookupTable, SpatialSubSampling, Sqrt, Square, TemporalConvolution, TemporalMaxPooling.
Test Plan: Imported from OSS
Differential Revision: D17628380
Pulled By: gchanan
fbshipit-source-id: a3ebd24765d00073e60212f6f664ec4a6d8c1d1b
