[Inductor] Fuse non-foreach ops with foreach ops without iterating over all subnodes (#106008)
Previously, when fusing a single node into a foreach op, the scheduler would iterate over each subnode and check if it can be fused, this PR adds a mapping so that the node to be fused with can be found more quickly by checking dependencies.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/106008
Approved by: https://github.com/jansel
