clk: qcom: rcg: Return failure for RCG update

BugLink: https://bugs.launchpad.net/bugs/1874045

commit 21ea4b62 upstream.

In case of update config failure, return -EBUSY, so that consumers could
handle the failure gracefully.
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lkml.kernel.org/r/1557339895-21952-2-git-send-email-tdas@codeaurora.orgSigned-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

drivers/clk/qcom/clk-rcg2.c

@@ -107,7 +107,7 @@ static int update_config(struct clk_rcg2 *rcg)
 	}
 
 	WARN(1, "%s: rcg didn't update its configuration.", name);
-	return 0;
+	return -EBUSY;
 }
 
 static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index)