Fixes for GCC 15.

--- CSSC-1.4.1/src/sccs.c	2019-05-07 12:40:13.000000000 +0100
+++ CSSC-1.4.1/src/sccs.c	2025-07-05 02:53:28.309239072 +0100
@@ -267,7 +267,6 @@
 
 /****************  End of Configuration Information  ****************/
 
-typedef char bool;
 #define TRUE    1
 #define FALSE   0
 
@@ -640,7 +639,6 @@
   if (p != NULL && p[0] != '\0')
     {
       register struct passwd *pw;
-      extern struct passwd *getpwnam();
       char buf[FBUFSIZ];
 
       if (p[0] == '/')