csky: Move static keyword to the front of declaration

Move the static keyword to the front of declaration of
csky_pmu_of_device_ids, and resolve the following compiler
warning that can be seen when building with warnings
enabled (W=1):

arch/csky/kernel/perf_event.c:1340:1: warning:
  ‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: NKrzysztof Wilczynski <kw@linux.com>
Signed-off-by: NGuo Ren <guoren@kernel.org>

arch/csky/kernel/perf_event.c

@@ -1337,7 +1337,7 @@ int csky_pmu_device_probe(struct platform_device *pdev,
 	return ret;
 }
 
-const static struct of_device_id csky_pmu_of_device_ids[] = {
+static const struct of_device_id csky_pmu_of_device_ids[] = {
 	{.compatible = "csky,csky-pmu"},
 	{},
 };