clk: Fix incorrect return type in clk.c

Return type of function clk_propagate_rate_change is a pointer.
But 0 was being returned. Change it to NULL.
Silences the following warning:
drivers/clk/clk.c:977:24: warning: Using plain integer as NULL pointer

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Reviewed-by: Pankaj Jangra <jangra.pankaj9@gmail.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 253792a46c08..5e8ffff99362 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1026,7 +1026,7 @@ static struct clk *clk_propagate_rate_change(struct clk *clk, unsigned long even
         int ret = NOTIFY_DONE;
 
         if (clk->rate == clk->new_rate)
-                return 0;
+                return NULL;
 
         if (clk->notifier_count) {
                 ret = __clk_notify(clk, event, clk->rate, clk->new_rate);