metal : add count_equal op (#18314)
* add count equal for metal
* remove trailing whitespace
* updated doc ops table
* changed shmem to i32
* added multi tg and templating
* removed BLAS support from Metal docs
* Apply suggestions from code review
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
* add memset to set dst to 0
* metal : cleanup
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Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
