mips: cavium: Replace DEFINE_SIMPLE_ATTRIBUTE with DEFINE_DEBUGFS_ATTRIBUTE

Fix the following coccicheck warning:
./arch/mips/cavium-octeon/oct_ilm.c:65:0-23: WARNING:
reset_statistics_ops should be defined with DEFINE_DEBUGFS_ATTRIBUTE
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/cavium-octeon/oct_ilm.c

@@ -62,7 +62,7 @@ static int reset_statistics(void *data, u64 value)
 	return 0;
 }
 
-DEFINE_SIMPLE_ATTRIBUTE(reset_statistics_ops, NULL, reset_statistics, "%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(reset_statistics_ops, NULL, reset_statistics, "%llu\n");
 
 static void init_debugfs(void)
 {