ARM: OMAP: Fix warning in clock.c

Fix warning:

arch/arm/mach-omap1/clock.c: In function
'omap1_clk_enable_generic':
arch/arm/mach-omap1/clock.c:499: warning: 'return' with no
value, in function returning non-void

Signed-off-by: Dirk Behme <dirk.behme_at_gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap1/clock.c

@@ -494,7 +494,7 @@ static int omap1_clk_enable_generic(struct clk *clk)
 		}
 	}
 
-	return;
+	return 0;
 }
 
 static void omap1_clk_disable_generic(struct clk *clk)