[S390] correct alignment of cpuid structure

The store-cpu-id instruction has a minimum alignment of 8. Reflect
that in the definition of struct cpuid.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/cpu.h b/arch/s390/include/asm/cpu.h
index 471234b..e0b6954 100644
--- a/arch/s390/include/asm/cpu.h
+++ b/arch/s390/include/asm/cpu.h
@@ -20,7 +20,7 @@
 	unsigned int ident   : 24;
 	unsigned int machine : 16;
 	unsigned int unused  : 16;
-} __packed;
+} __attribute__ ((packed, aligned(8)));
 
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_S390_CPU_H */