clk: renesas: rcar-gen2: Delete error message for failed memory allocation

The script "checkpatch.pl" pointed information out like the following.

WARNING: Possible unnecessary 'out of memory' message

Thus fix affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/clk/renesas/clk-rcar-gen2.c

@@ -423,7 +423,6 @@ static void __init rcar_gen2_cpg_clocks_init(struct device_node *np)
 		/* We're leaking memory on purpose, there's no point in cleaning
 		 * up as the system won't boot anyway.
 		 */
-		pr_err("%s: failed to allocate cpg\n", __func__);
 		return;
 	}