[SPARC64]: Don't double-export synchronize_irq.

It is done by the generic IRQ layer now.
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/sparc64_ksyms.c

@@ -125,9 +125,6 @@ EXPORT_SYMBOL(__write_lock);
 EXPORT_SYMBOL(__write_unlock);
 EXPORT_SYMBOL(__write_trylock);
 
-/* Hard IRQ locking */
-EXPORT_SYMBOL(synchronize_irq);
-
 #if defined(CONFIG_MCOUNT)
 extern void _mcount(void);
 EXPORT_SYMBOL(_mcount);