arch/riscv: Remove supervisor_trap_entry

coreboot only maintains a single trap entry, because it only runs in
machine mode.

Change-Id: I7324d9c8897d5c4e9d4784e7bc2a055890eab698
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/22595
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
1 file changed