[PATCH] arch/x86/lib/cpu-c - missing prototypes

["Valdis Klētnieks" <valdis.kletnieks@vt.edu>]

When building with W=1, we get warnings about missing prototypes:

  CC      arch/x86/lib/cpu.o
arch/x86/lib/cpu.c:5:14: warning: no previous prototype for 'x86_family' [-Wmissing-prototypes]
    5 | unsigned int x86_family(unsigned int sig)
      |              ^~~~~~~~~~
arch/x86/lib/cpu.c:18:14: warning: no previous prototype for 'x86_model' [-Wmissing-prototypes]
   18 | unsigned int x86_model(unsigned int sig)
      |              ^~~~~~~~~
arch/x86/lib/cpu.c:33:14: warning: no previous prototype for 'x86_stepping' [-Wmissing-prototypes]
   33 | unsigned int x86_stepping(unsigned int sig)
      |              ^~~~~~~~~~~~

Add the proper include file so the prototypes are there.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>

diff --git a/arch/x86/lib/cpu.c b/arch/x86/lib/cpu.c
index 04967cdce5d1..7ad68917a51e 100644
--- a/arch/x86/lib/cpu.c
+++ b/arch/x86/lib/cpu.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 #include <linux/types.h>
 #include <linux/export.h>
+#include <asm/cpu.h>
 
 unsigned int x86_family(unsigned int sig)
 {