Add --reload option to sesman

Adds a --reload switch to sesman and plumbs this in
to systemctl reload xrdp-sesman.service

common/os_calls.c

@@ -3043,6 +3043,18 @@ g_sigterm(int pid)
 #endif
 }
 
+/*****************************************************************************/
+/* does not work in win32 */
+int
+g_sighup(int pid)
+{
+#if defined(_WIN32)
+    return 0;
+#else
+    return kill(pid, SIGHUP);
+#endif
+}
+
 /*****************************************************************************/
 /* returns 0 if ok */
 /* the caller is responsible to free the buffs */

common/os_calls.h

@@ -192,6 +192,7 @@ char    *g_getenv(const char *name);
 int      g_exit(int exit_code);
 int      g_getpid(void);
 int      g_sigterm(int pid);
+int      g_sighup(int pid);
 int      g_getuser_info(const char *username, int *gid, int *uid, char **shell,
                         char **dir, char **gecos);
 int      g_getgroup_info(const char *groupname, int *gid);