init/version.c: define version_string only if CONFIG_KALLSYMS is not defined

int Version_* is only used with ksymoops, which is only needed (according
to README and Documentation/Changes) if CONFIG_KALLSYMS is NOT defined.
Therefore this patch defines version_string only if CONFIG_KALLSYMS is not
defined.

Signed-off-by: Daniel Guilak <[e-mail]>
Cc: Randy Dunlap <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

init/version.c

···
 #include <linux/utsrelease.h>
 #include <linux/version.h>
 
+#ifndef CONFIG_KALLSYMS
 #define version(a) Version_ ## a
 #define version_string(a) version(a)
 
 extern int version_string(LINUX_VERSION_CODE);
 int version_string(LINUX_VERSION_CODE);
+#endif
 
 struct uts_namespace init_uts_ns = {
 	.kref = {