powerpc/jump_label: use HAVE_JUMP_LABEL?

CONFIG_JUMP_LABEL doesn't ensure HAVE_JUMP_LABEL, if it
is not the case use maintainers's own mutex to guard
the modification of global values.

Signed-off-by: Zhouyi Zhou <yizhouzhou@ict.ac.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/powernv/opal-tracepoints.c

@@ -2,7 +2,7 @@
 #include <linux/jump_label.h>
 #include <asm/trace.h>
 
-#ifdef CONFIG_JUMP_LABEL
+#ifdef HAVE_JUMP_LABEL
 struct static_key opal_tracepoint_key = STATIC_KEY_INIT;
 
 void opal_tracepoint_regfunc(void)