Arm backend: qdq folding support for remaining operators (#7340)

* Add TOSA table as custom edge op

Edge operators that are lowered to TOSA TABLEs are convereted to a
custom edge IR table-op.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: I147008c30b9b46c7b8ae1a1c15bc540fea614a69

* Add support for concat q/dq folding

This is a special case where node.args can be lists with many incoming
dq-nodes.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: Icf511a8bdeaaffb597b18455ab7f1fbd947ce3ca

* Increase q/dq folding coverage

Add support for q/dq folding of more operators such as hardtanh,
maxpool2d, mul, relu, select, sub, to_copy.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: Ifdabda4c927dade41c000859054696844c546f7b

* Add support for sum q/dq folding

sum is retraced to an int64 dtype of operator after q/dq folding.
This patch adds a pass to manually force the dtype to be int8.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: Ifa737a398c5a878d52cd76a2392499905da085ce

* Complete q/dq folding coverage

Add support for q/dq folding for the remaining supported ops in Arm
backend.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: I9012b4a501ce018c9771c729706be3b031a5c7ae

* Remove is_quant_node from NodeVisitor.define_node

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: Ibb17add461dc79e022a7f4accde29f9f9d61b16d

* Fix pyre issues

Address issues from pyre and add similar # pyre-ignores as in
https://github.com/pytorch/executorch/pull/7362.

Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>
Change-Id: I6feaa611dcd539b3b0d21a6a7dd696ef7db691ef

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Signed-off-by: Oscar Andersson <oscar.andersson@arm.com>