powerpc: Make prom_init.c suitable for both 32-bit and 64-bit

Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c
index e01cda1..75b487f 100644
--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -1968,9 +1968,9 @@
 	extern char _stext[];
 	unsigned long hdr;
 	u32 getprop_rval;
+	unsigned long offset = reloc_offset();
 
 #ifdef CONFIG_PPC32
-	unsigned long offset = reloc_offset();
 	reloc_got2(offset);
 #endif