Revert D28041140: [pytorch][PR] Adding vector_norm to the C++ API
Test Plan: revert-hammer
Differential Revision:
D28041140 (https://github.com/pytorch/pytorch/commit/fda856194457b3e3ea0ea7364f752d85ba9b9a21)
Original commit changeset: 65ab32efbcf9
fbshipit-source-id: ce69c6c1f2076c24f96d1f678ace415b22b2332c
