Make liblog headers compile stand-alone.

Test: process liblog headers individually with header-abi-dumper.

Test: mm -j64

Bug: 66971285

Change-Id: If7dec611b84eb9fa8e1e5a974b444d4ddf54759a
diff --git a/liblog/include/log/log_safetynet.h b/liblog/include/log/log_safetynet.h
index b8ca475..07e8c8a 100644
--- a/liblog/include/log/log_safetynet.h
+++ b/liblog/include/log/log_safetynet.h
@@ -10,6 +10,8 @@
 #ifndef _LIBS_LOG_SAFETYNET_H
 #define _LIBS_LOG_SAFETYNET_H
 
+#include <stdint.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif