lib: sbi: sse: check handler entry to belong to supervisor mode

When registering an SSE event, check for the handler_entry_pc to belong
to supervisor mode domain using sbi_domain_check_addr_range().

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reported-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>