[To backport] [blocks] fix name mangling-unmangling in RecurrentStack
[To backport] [blocks] fix name mangling-unmangling in RecurrentStack

nke001/attention-lvcsr,rizar/attention-lvcsr,nke001/attention-lvcsr,nke001/attention-lvcsr,rizar/attention-lvcsr,nke001/attention-lvcsr,nke001/attention-lvcsr,rizar/attention-lvcsr,rizar/attention-lvcsr,rizar/attention-lvcsr