Align SFP key names with new standard defined in https://github.com/Azure/sonic-platform-common/pull/97
- hardwarerev -> hardware_rev
- serialnum -> serial
- manufacturename -> manufacturer
- modelname -> model
- Connector -> connector
- Skip thermalctld in DellEMC S6000, S6100, Z9100 and Z9264 platforms.
- Change the return type of thermal Platform APIs in DellEMC S6000, S6100, Z9100 and Z9264 platforms to 'float'.
- Sfp,Eeprom,Chassis(transceiver change event) support added for z9264f Platform 2.0 API
- Added Interrupt handler to SFP change event in dell_z9264f_fpga_ocores.c
- Fixed few indentation and offset issues in sfputil.py for z9264f
