csky: fixup compile error with CPU 810.

This bug is from commit f553aa1c ("csky: fixup relocation error with
807 & 860").

I forgot to compile with 810 for that patch.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>