* generate static graph code of some ops

* change the default value of 'num' of 'unstack'

* revert the pow

* fix the 'real' 'imag' op error because of 'complex'

* fix the code according to review

* normalize yaml op label

* revert op_compat yaml change

* fix prelu and rnn compat problem

* replace api by op

* move yaml to phi

* fix undef var error

* move trace into api.yaml

* add trace unittest

* fix trace test

* fix generate op