[PATCH] raid6: fix riscv symbol undeclared warnigns

[Nam Cao]

Ben Dooks <ben.dooks at codethink.co.uk> writes:
> The riscv rvv.c file is missing the include of pq_arch.h
> which defines all the exported functions. Include this
> to remove the following sparse warnings:
>
> lib/raid/raid6/riscv/rvv.c:1225:1: warning: symbol 'raid6_rvvx1' was not declared. Should it be static?
> lib/raid/raid6/riscv/rvv.c:1226:1: warning: symbol 'raid6_rvvx2' was not declared. Should it be static?
> lib/raid/raid6/riscv/rvv.c:1227:1: warning: symbol 'raid6_rvvx4' was not declared. Should it be static?
> lib/raid/raid6/riscv/rvv.c:1228:1: warning: symbol 'raid6_rvvx8' was not declared. Should it be static?
>
> Signed-off-by: Ben Dooks <ben.dooks at codethink.co.uk>

Reviewed-by: Nam Cao <namcao at linutronix.de>