RISCV: Remove hartid and DTB parsing from the boot code.

.licenseignore

include/arch/riscv/arch/kernel/boot.h

include/plat/spike/plat/machine/fdt.h

src/arch/riscv/head.S

src/arch/riscv/kernel/boot.c

src/plat/spike/config.cmake

src/plat/spike/machine/fdt.c

src/plat/spike/machine/hardware.c