Replaced setuid(void) callback (which didn't work right anyway) with

FreeBSD-tested seteuid(BOOL user) (set effective user-id) callback.
Deuce's mod.

src/sbbs3/ftpsrvr.h

@@ -69,7 +69,7 @@ typedef struct {
     void	(*thread_up)(BOOL up);
 	void	(*socket_open)(BOOL open);
     void	(*client_on)(BOOL on, int sock, client_t*, BOOL update);
-    BOOL	(*setuid)(void);
+    BOOL	(*seteuid)(BOOL user);
     void	(*reserved_fptr3)(void);
     void	(*reserved_fptr2)(void);
     void	(*reserved_fptr1)(void);

src/sbbs3/mailsrvr.h

@@ -71,7 +71,7 @@ typedef struct {
     void	(*thread_up)(BOOL up);
 	void	(*socket_open)(BOOL open);
     void	(*client_on)(BOOL on, int sock, client_t*, BOOL update);
-    BOOL	(*setuid)(void);
+    BOOL	(*seteuid)(BOOL user);
     void	(*reserved_fptr3)(void);
     void	(*reserved_fptr2)(void);
     void	(*reserved_fptr1)(void);

src/sbbs3/services.h

@@ -62,7 +62,7 @@ typedef struct {
     void	(*thread_up)(BOOL up);
 	void	(*socket_open)(BOOL open);
     void	(*client_on)(BOOL on, int sock, client_t*, BOOL update);
-    BOOL	(*setuid)(void);
+    BOOL	(*seteuid)(BOOL user);
     void	(*reserved_fptr3)(void);
     void	(*reserved_fptr2)(void);
     void	(*reserved_fptr1)(void);

src/sbbs3/startup.h

@@ -75,7 +75,7 @@ typedef struct {
     void	(*thread_up)(BOOL up);
 	void	(*socket_open)(BOOL open);
     void	(*client_on)(BOOL on, int sock, client_t*, BOOL update);
-    BOOL	(*setuid)(void);	// Set Unix uid for thread
+    BOOL	(*seteuid)(BOOL user);	// Set Unix uid for thread
     void	(*reserved_fptr3)(void);
     void	(*reserved_fptr2)(void);
     void	(*reserved_fptr1)(void);