Fix compilation on musl C systems due to missing sys/time.h header.

Thanks to maxice8.

ChangeLog.txt

@@ -1,3 +1,10 @@
+1.6.1 - 201905xx
+================
+
+Clients:
+- Fix compilation on musl C systems due to missing sys/time.h header.
+
+
 1.6 - 20190417
 ==============
 

client/client_shared.h

@@ -19,6 +19,12 @@ Contributors:
 
 #include <stdio.h>
 
+#ifdef WIN32
+#  include <winsock2.h>
+#else
+#  include <sys/time.h>
+#endif
+
 /* pub_client.c modes */
 #define MSGMODE_NONE 0
 #define MSGMODE_CMD 1