fix possible usage of uninitialized memory

http://bugs.gentoo.org/80286

--- bsd-finger-0.17/finger/lprint.c
+++ bsd-finger-0.17/finger/lprint.c
@@ -100,7 +100,7 @@
 	 *	office, office phone, home phone if available
 	 */
 	xprintf("Login: %-15s\t\t\tName: %s\nDirectory: %-25s",
-		pn->name, pn->realname, pn->dir);
+		pn->name, pn->realname ? pn->realname : "", pn->dir);
 	xprintf("\tShell: %-s\n", *pn->shell ? pn->shell : _PATH_BSHELL);
 
 	/*
--- bsd-finger-0.17/finger/util.c
+++ bsd-finger-0.17/finger/util.c
@@ -149,6 +149,8 @@
 		rname[j] = 0;
 
 		pn->realname = rname;
+	} else {
+		pn->realname = NULL;
 	}
 
 	pn->office =      fields[1] ? strdup(fields[1]) : NULL;