* - Added reorder support for rnn weights_layer/iter

* i) fixed compilation issues ii) working but still observing precision error

* i) fixed failing rnn unit test for DEX ii) refactored workspace in RNN mkldnn emitter

* i) added support for src reorder to TNC from NTC

* reorder support for rnn output fron NTC to TNC

* - added support for rnn weight reorder ldgoi -> ldigo
- code refactor for lstm/rnn kernel in mkldnn emitter

* - refactor rnn mkldnnn kernel, change variable names

* fix RNN codegen kernel

* disbale layer rnn fusion pass, to test CI

* method to validate recurrent rnn inputs

* add correlated macthes for Recurrent RNN PM

* - simplify reorder logic for rnn_weights
- fix graph pattern for fusing rnn cell across time steps

* do weights reorders in rnn timesteps fusion

* refactored LSTM graph pass

* - Bug fix for finding the lstm inputs determenstically
- Refactored LSTM graph pass to single pass
- made changes to LSTM RNN time step fusion graph pass

* - use replace_node instead of replace_output in Lstm_step_wise fusion graph pass

* fix compilation error

* Fix GNMT rnn fusion

* check if the node is in use before replacing in RNN graph passes

*  i) fix style ii) fix topo sort issue in RNN graph pass

* style fix

* fix bug in simplify_concat pass

* replaces Lstm1 -> {GOE1, GOE2} -> {Slice1, Slice2} -> Concat -> Lstm2 with Lstm1 -> Lstm2

* cse for convert layout

* addressed PR comments

* - optimization pass to remove  Lstm1 -> {GOE1, GOE2} -> {Slice1, Slice2} -> Lstm2
- conditional fusing of LSTM cells only for the decoder

* made changes to multi layer RNN fusion callback

* fix asserts in RNN op

* - added support to fuse layers when slc=dlc for RNN cells
- bug fix on the sanity checks for RNN Op

* - support RNN layer fusion till slc = dlc
- bug fixes in multi layer rnn fusion call back

* capture reshape in the RNN weights

* Addressed PR comments

* - added comments in multi layer PM call back
- fuse only if slc == DLC across layers

* restore deleted 3_lstm_cell_forward.json file

* fix typo

* fix failing unit tets

* When processing in place slice, do not change the offset of the slice node if the argument pointer comes from function input.

* Address PR feedback: process in place slice after propagating in place input.

* Set INTERMEDIATE role before propagating in place input.

* Do not add temporaries to the variable name map before propagating in place input in codegen.

* Fix a bug in codegen.

* Fix a bug in codegen slice.

* reenable disabled rnn unit test

* fix compiler error

* - bug fix in the slicing logic for the layer fused rnn cell
- fix failing rnn unit test

* - Addressed PR comments
- removed redundant checks from the rnn graph pass
- simplified rnn call back replace node logic

* - added new multilayer rnn *.json file
- fix test case

* [PRIVATE BRANCH] Style fixes (#2080)

* Style fixes

* change order of lstm gates

* WIP bi rnn

* [PRIVATE BRANCH] Jbobba/rnn fusion review (#2113)

* Style fixes for single-layer RNN fusion

* Style fixes to multi-layer RNN

* added callback routine for bi-directional rnn

* fix rnn op ctor, rnn mkldnn emitter to accomodate bi directional rnn

* style fix

* added helper function for rnn's to query direction and cell_type

* fix clang error

* - unit test case for bi rnn fusion
- style fix

* - updated bi-rnn graph pass to handle reverse and reverse_seq ops in the predicate
- added bi-rnn inter v/s cpu unit test case
- add support to in mkldnn_utils to create_md with tnc/ntc format

* - added enum type to deduce rnn_type

* Addressed PR comments
    - handle reshapes from {t, n, c} to {n, t, c} in the graph pass

* fix style

* fix clang error

* fix style

* i) move enum specific to rnn to seperate header