frv: build fix

In file included from /usr/src/linux-2.6-2/net/ipv4/ip_input.c:118:

include2/asm/system.h:245: error: parse error before "__cmpxchg_32"
include2/asm/system.h:245: error: parse error before '*' token
include2/asm/system.h:245: warning: type defaults to `int' in declaration of `__cmpxchg_32'
include2/asm/system.h:245: warning: function declaration isn't a prototype
include2/asm/system.h:245: warning: data definition has no type or storage class

Signed-off-by: Peter Zijlstra <[e-mail]>
Acked-by: David Howells <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/asm-frv/system.h

···
 #ifndef _ASM_SYSTEM_H
 #define _ASM_SYSTEM_H
 
+#include <linux/types.h>
 #include <linux/linkage.h>
 
 struct thread_struct;