Use VmmTblAPI instead of vmm_config.

VmmTbl now inherits from asynPortDriver instead of FrontEndBase.
It has VmmTblAPI as a class component.

Thus, everything that used pRMM->foo(); such as pRMM->setStringParam(addr_list, vmmHybFwVersion_[hyb], pVMMConfig.readFwVersion(hyb).c_str());
are simply foor(); (equivalent to this->foo();)

Everything that used pVMMConfig.foo(); now uses pVmmTblAPI->foo();

configFEN had its name changed to configFE since the last configFE did
nothing.
Old configFE was removed.

In the end, findRegister() was not moved to VmmTblAPI because it seems
to be searching for a given register name based on an epics parameter.