Enable arm64 convolution for fbgemm through the reference convolution APIs

[mcfi]

Summary: This diff adds convolution support to arm64 fbgemm by reusing existing reference implementations.

1. Introduced conv_requant_ref that invokes the reference conv_ref and requantize_u8acc32_ref and added it in places where only x86 conv implementations are available.
2. Changed weights matrix packing to basically do nothing or call transposeConvWeights.

This diff unblocks fbgemm users' convolution code on Arm64. We plan to add follow-up diffs to optimize each kind of convolution (e.g., depthwise, directconv, etc.)

Differential Revision: D86548699

[meta-codesync[bot]]

@mcfi has exported this pull request. If you are a Meta employee, you can view the originating Diff in D86548699.