MIPS: Remove duplicated #include

Remove duplicated #include in arch/mips/kernel/smp.c.
Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/smp.c

@@ -32,7 +32,6 @@
 #include <linux/cpumask.h>
 #include <linux/cpu.h>
 #include <linux/err.h>
-#include <linux/smp.h>
 
 #include <asm/atomic.h>
 #include <asm/cpu.h>