plnsub: Add missing newline to two messages

The two "while it is carrying a nuclear weapon" messages lack
newlines.  Add them.  Screwed up in commit a269cdd, v4.3.23.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>

src/lib/commands/miss.c

@@ -29,7 +29,7 @@
  *  Known contributors to this file:
  *     Thomas Ruschak, 1992
  *     Steve McClure, 2000
- *     Markus Armbruster, 2005-2013
+ *     Markus Armbruster, 2005-2016
  */
 
 #include <config.h>
@@ -244,7 +244,8 @@ mission(void)
 	}
 
 	if (type == EF_PLANE && nuk_on_plane((struct plnstr *)gp) >= 0) {
-	    pr("%s can't perform a mission while it carries a nuclear weapon",
+	    pr("%s can't perform a mission"
+	       " while it is carrying a nuclear weapon\n",
 	       unit_nameof(gp));
 	    continue;
 	}

src/lib/subs/plnsub.c

@@ -30,7 +30,7 @@
  *     Dave Pare, 1986
  *     Ken Stevens, 1995
  *     Steve McClure, 1998-2000
- *     Markus Armbruster, 2004-2015
+ *     Markus Armbruster, 2004-2016
  */
 
 #include <config.h>
@@ -725,7 +725,7 @@ pln_equip(struct plist *plp, struct ichrstr *ip, char mission)
 		needed = 0;
 	    else {
 		pr("%s can't fly this mission"
-		   " while it is carrying a nuclear weapon",
+		   " while it is carrying a nuclear weapon\n",
 		   prplane(pp));
 		return -1;
 	    }