arch/riscv: Add misc.c to bootblock/romstage to get udelay()

The uart8250mem driver needs it.

Change-Id: I09e6a17cedf8a4045f008f5a0d225055d745e8db
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/15147
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
1 file changed