Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/perf/arch/common.h b/tools/perf/arch/common.h
index 2167001..e965ed8 100644
--- a/tools/perf/arch/common.h
+++ b/tools/perf/arch/common.h
@@ -2,8 +2,11 @@
 #ifndef ARCH_PERF_COMMON_H
 #define ARCH_PERF_COMMON_H
 
-#include "../util/env.h"
+#include <stdbool.h>
+
+struct perf_env;
 
 int perf_env__lookup_objdump(struct perf_env *env, const char **path);
+bool perf_env__single_address_space(struct perf_env *env);
 
 #endif /* ARCH_PERF_COMMON_H */