ASoC: tegra: s/IS_ERR_OR_NULL/IS_ERR/ for clk_get_sys

A recent discussion on linux-arm-kernel noted that the value returned by
clk_get_sys is an opaque token, and not strictly a pointer; it is
meaningful only to the clock API, clients should not dereference the value,
and the clock API must accept any non-IS_ERR value it returned.

Hence, only IS_ERR is appropriate to interpret the result, not
IS_ERR_OR_NULL.

I checked that clk_get_sys in both ASoC's for-next and Tegra's for-next
do behave as described; NULL is not returned in the case of error.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/tegra/tegra_i2s.c b/sound/soc/tegra/tegra_i2s.c
index 1730509..6d66878 100644
--- a/sound/soc/tegra/tegra_i2s.c
+++ b/sound/soc/tegra/tegra_i2s.c
@@ -385,7 +385,7 @@
 
 	snprintf(clk_name, sizeof(clk_name), DRV_NAME ".%d", pdev->id);
 	i2s->clk_i2s = clk_get_sys(clk_name, NULL);
-	if (IS_ERR_OR_NULL(i2s->clk_i2s)) {
+	if (IS_ERR(i2s->clk_i2s)) {
 		pr_err("Can't retrieve i2s clock\n");
 		ret = PTR_ERR(i2s->clk_i2s);
 		goto err_free;