string constants

<Someone> wrote:
> Linux, Redhat 7.1 nethack 3.4.0
>
>Please see attached patch file.
>
>I'm attempting to move more stuff into the "read-only" area, in
>preparation for a port to another OS.

src/do.c

@@ -1233,13 +1233,13 @@ boolean at_stairs, falling, portal;
 	}
 
 	if (familiar) {
-	    static const char *fam_msgs[4] = {
+	    static const char * const fam_msgs[4] = {
 		"You have a sense of deja vu.",
 		"You feel like you've been here before.",
 		"This place %s familiar...",
 		0	/* no message */
 	    };
-	    static const char *halu_fam_msgs[4] = {
+	    static const char * const halu_fam_msgs[4] = {
 		"Whoa!  Everything %s different.",
 		"You are surrounded by twisty little passages, all alike.",
 		"Gee, this %s like uncle Conan's place...",