Use <stdlib.h> instead of the deprecated and non-portable <malloc.h>.

dlls/icmp/icmp_main.c

@@ -32,7 +32,7 @@
 #endif
 
 #include <sys/time.h>
-#include <malloc.h>
+#include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 #include <unistd.h>