genirq: remove redundant if condition

Impact: cleanup

The code is only compiled if CONFIG_GENERIC_HARDIRQS=y so another
check for this define in the code is redundant. Remove it.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

kernel/irq/manage.c

@@ -15,7 +15,7 @@
 
 #include "internals.h"
 
-#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
+#ifdef CONFIG_SMP
 cpumask_var_t irq_default_affinity;
 
 /**