[llvm][STLExtras] Move the algorithm `interleave*` methods from MLIR to LLVM

Authored by rriddle on Apr 14 2020, 2:53 PM.


[llvm][STLExtras] Move the algorithm interleave* methods from MLIR to LLVM

These have proved incredibly useful for interleaving values between a range w.r.t to streams. After this revision, the mlir/Support/STLExtras.h is empty. A followup revision will remove it from the tree.

Differential Revision: https://reviews.llvm.org/D78067