forked from Mirrors/opensbi

Add Ssdbltrp trap handler support for S-mode double trap handling. If the trap is received while in VS-mode, then the trap is redirected to S-mode. If caught while in HS-mode, then an error is returned to the top trap handler which will panic. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Samuel Holland <samuel.holland@sifive.com>