target/riscv: Do not abuse DEFINE_PROP_END_OF_LIST

target/riscv: Do not abuse DEFINE_PROP_END_OF_LIST

These are not arrays of Property and had no business
using DEFINE_PROP_END_OF_LIST.  Use plain { } instead.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Link: https://lore.kernel.org/r/20241218134251.4724-20-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>