Add missing headers for compilation on x86 targets

Change-Id: I5f4dc797b353a0f01fa00d38375ec303bf863254
diff --git a/libsysutils/src/ServiceManager.cpp b/libsysutils/src/ServiceManager.cpp
index 60b161a..1ba6ef0 100644
--- a/libsysutils/src/ServiceManager.cpp
+++ b/libsysutils/src/ServiceManager.cpp
@@ -1,4 +1,5 @@
 #include <errno.h>
+#include <string.h>
 
 #include <sysutils/ServiceManager.h>