liblog: drop use of sys/cdefs.h

(cherry picked from commit c96a44888a50fdc6155cb1a7fa8e37bee00fafc0)

Change-Id: I44ea5d6b572e3712c301e6ebf4b34e6225d7e18b
diff --git a/include/log/log.h b/include/log/log.h
index 3ae3086..e3ecc69 100644
--- a/include/log/log.h
+++ b/include/log/log.h
@@ -28,7 +28,6 @@
 #ifndef _LIBS_LOG_LOG_H
 #define _LIBS_LOG_LOG_H
 
-#include <sys/cdefs.h>
 #include <sys/types.h>
 #ifdef HAVE_PTHREADS
 #include <pthread.h>
@@ -40,7 +39,9 @@
 #include <log/logd.h>
 #include <log/uio.h>
 
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 // ---------------------------------------------------------------------
 
@@ -558,6 +559,8 @@
 int __android_log_buf_write(int bufID, int prio, const char *tag, const char *text);
 int __android_log_buf_print(int bufID, int prio, const char *tag, const char *fmt, ...);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 
 #endif // _LIBS_CUTILS_LOG_H