powerpc: add finit_module syscall.

(This is just for Acks: this won't work without the actual syscall patches,
 sitting in my tree for -next at the moment).

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 8408387..d0b27f8 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -356,3 +356,4 @@
 SYSCALL_SPU(setns)
 COMPAT_SYS(process_vm_readv)
 COMPAT_SYS(process_vm_writev)
+SYSCALL(finit_module)