x86/lib/cpu: Address missing prototypes warning

[ Upstream commit 04f5bda ]

When building with W=1, warnings about missing prototypes are emitted:

  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 <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/r/42513.1565234837@turing-police
Signed-off-by: Sasha Levin <[email protected]>

Author: valdisk

arch/x86/lib/cpu.c

@@ -1,5 +1,6 @@
 #include <linux/types.h>
 #include <linux/export.h>
+#include <asm/cpu.h>
 
 unsigned int x86_family(unsigned int sig)
 {