fix another brown paper bag bug introduced with compile time loglevel

__pr_printk is a define which uses a local variable 'ret'. This
means that whenever someone does a pr_*("ret: %d\n", ret);
ret will be 0.

Fix this by writing this without a local variable.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

include/printk.h

@@ -46,10 +46,7 @@ int dev_printf(const struct device_d *dev, const char *format, ...)
 
 #define __pr_printk(level, format, args...) \
 	({	\
-		int ret = 0;	\
-		if (level <= LOGLEVEL) \
-			ret = printk(format, ##args);	\
-		ret;					\
+		(level) <= LOGLEVEL ? printk((format), ##args) : 0; \
 	 })
 
 #ifndef pr_fmt