Updated sulogin.c to pull in crypt.h as it is a new, undocumented

dependency on Fedora 28.
Confirmed we can still build on other/older platforms.

doc/Changelog

@@ -35,6 +35,13 @@ sysvinit (2.90) UNRELEASED; urgency=low
       Added .gitignore files to avoid git tracking object files.
       Removed old start-stop-daemon from contrib directory.
       (Patches provided by Guillem Jover.)
+    * Cleaned up most warnings generated by GCC 7 & 8. We still
+      get some from faulty "nonstring" reports, but silencing them on
+      GCC 8 results in more warnings on GCC 7 and Clang, so leaving them
+      for now.
+    * Fixed compile error on Fedora 28 where crypt won't build due to
+      undocumented dependency change.
+
 
 sysvinit (2.89) world; urgency=low
 

src/sulogin.c

@@ -39,6 +39,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <crypt.h>    /* added to make this compile on Fedora 28 */
 #include <fcntl.h>
 #include <signal.h>
 #include <pwd.h>