Resolved minor bug in minimize accumulator width

need to do things different if MultiThreshold is the final node
in the graph (producing top-level output)

This reverts commit 7f6d9343.

Support 1D MaxPool

Merge branch 'feature/maxpool_1d' of https://github.com/fpjentzsch/finn into fpjentzsch-feature/maxpool_1d

# Conflicts:
#	src/finn/custom_op/fpgadataflow/upsampler.py
#	src/finn/transformation/fpgadataflow/convert_to_hls_layers.py