Quiet a gcc "used uninitialized in this function" false positive.

compat/pw_dup.c

@@ -67,7 +67,7 @@ pw_dup(const struct passwd *pw)
 {
 	size_t nsize = 0, psize = 0, gsize = 0, dsize = 0, ssize = 0, total;
 #ifdef HAVE_LOGIN_CAP_H
-	size_t csize;
+	size_t csize = 0;
 #endif
 	struct passwd *newpw;
 	char *cp;