L6470 SPI daisy chain support (#12895)

Marlin/Configuration_adv.h

Marlin/src/HAL/shared/HAL_spi_L6470.cpp

Marlin/src/Marlin.cpp

Marlin/src/Marlin.h

Marlin/src/config/default/Configuration_adv.h

...n/src/config/examples/3DFabXYZ/Migbot/Configuration_adv.h

...src/config/examples/AlephObjects/TAZ4/Configuration_adv.h

Marlin/src/config/examples/Anet/A2/Configuration_adv.h

Marlin/src/config/examples/Anet/A2plus/Configuration_adv.h

Marlin/src/config/examples/Anet/A6/Configuration_adv.h

Marlin/src/config/examples/Anet/A8/Configuration_adv.h

Marlin/src/config/examples/ArmEd/Configuration_adv.h

...c/config/examples/BIBO/TouchX/cyclops/Configuration_adv.h

...c/config/examples/BIBO/TouchX/default/Configuration_adv.h

Marlin/src/config/examples/BQ/Hephestos/Configuration_adv.h

...in/src/config/examples/BQ/Hephestos_2/Configuration_adv.h

Marlin/src/config/examples/BQ/WITBOX/Configuration_adv.h

Marlin/src/config/examples/Cartesio/Configuration_adv.h

...in/src/config/examples/Creality/CR-10/Configuration_adv.h

...n/src/config/examples/Creality/CR-10S/Configuration_adv.h