[S390] ptrace: no extern declarations for userspace

/include/asm/ptrace.h:275: extern's make no sense in userspace
/include/asm/ptrace.h:279: extern's make no sense in userspace
/include/asm/ptrace.h:280: extern's make no sense in userspace

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 5396f9f..8920025 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -272,12 +272,15 @@
 #define PSW_ASC_SECONDARY	0x0000800000000000UL
 #define PSW_ASC_HOME		0x0000C00000000000UL
 
-extern long psw_user32_bits;
-
 #endif /* __s390x__ */
 
+#ifdef __KERNEL__
 extern long psw_kernel_bits;
 extern long psw_user_bits;
+#ifdef CONFIG_64BIT
+extern long psw_user32_bits;
+#endif
+#endif
 
 /* This macro merges a NEW PSW mask specified by the user into
    the currently active PSW mask CURRENT, modifying only those