ggml-hexagon: add PAD op HVX kernel (#23078)
* ggml-hexagon: add PAD op HVX kernel
Implements GGML_OP_PAD on the Hexagon HTP backend using HVX vectorized
kernels. Supports zero-padding and circular padding across all 4 tensor
dimensions.
* hex-ggml: remove duplicate op cases (merge conflict)
* hex-pad: fix editorconfig checks and macro alignment
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Co-authored-by: Max Krasnyansky <maxk@qti.qualcomm.com>