Fix incorrect header include. The strcasecmp function is defined in

<strings.h>, not <string.h>.

Author: jdelvare

dmiopt.c

@@ -20,7 +20,7 @@
  */
 
 #include <stdio.h>
-#include <string.h>
+#include <strings.h>
 #include <stdlib.h>
 #include <getopt.h>