[POWERPC] Make doc comments extractable

We don't have much in the way of doc comments, but some of those we do have
don't work because they start with "/***" or "/*", not "/**" which is what
kernel-doc requires.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index 9855820..26a6a3b 100644
--- a/arch/powerpc/sysdev/i8259.c
+++ b/arch/powerpc/sysdev/i8259.c
@@ -224,7 +224,7 @@
 	.xlate = i8259_host_xlate,
 };
 
-/****
+/**
  * i8259_init - Initialize the legacy controller
  * @node: device node of the legacy PIC (can be NULL, but then, it will match
  *        all interrupts, so beware)