x86, microcode, amd: Fix missing static declaration

Make locally used variable static.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Link: http://lkml.kernel.org/r/1406146251-8540-1-git-send-email-hmh@hmh.eng.br
Signed-off-by: Borislav Petkov <bp@suse.de>

arch/x86/kernel/cpu/microcode/amd_early.c

@@ -27,7 +27,7 @@ static u32 ucode_new_rev;
 u8 amd_ucode_patch[PATCH_MAX_SIZE];
 static u16 this_equiv_id;
 
-struct cpio_data ucode_cpio;
+static struct cpio_data ucode_cpio;
 
 /*
  * Microcode patch container file is prepended to the initrd in cpio format.