feat: add new `sin` and `cos` operators (ggml/919)

feat: add new `sin` and `cos` operators (ggml/919)

* ggml : add sin/cos operators

* ggml-cuda : add sin/cos operators

* ggml : add corresponding tests for sin/cos

* ggml : add backward computation for sin/cos operators

* ggml-vulkan : add sin/cos operators

* ggml-vulkan : add sin/cos shader source

* metal : add sin, cos

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Co-authored-by: Georgi Gerganov <redacted>