CASTOR-5107 Improve the const correctness of Cns_queryclass()

Fixed.

h/Cns_api.h

@@ -275,7 +275,7 @@ EXTERN_C Cns_DIR *Cns_opendir (const char *);
 EXTERN_C Cns_DIR *Cns_opendirg (const char *, const char *);
 EXTERN_C Cns_DIR *Cns_opendirxg (char *, const char *, const char *);
 EXTERN_C int Cns_ping (char *, char *);
-EXTERN_C int Cns_queryclass (char *, int, char *, struct Cns_fileclass *);
+EXTERN_C int Cns_queryclass (const char *, int, const char *, struct Cns_fileclass *);
 EXTERN_C struct dirent *Cns_readdir (Cns_DIR *);
 EXTERN_C struct Cns_direncomm *Cns_readdirc (Cns_DIR *);
 EXTERN_C struct Cns_direnstatg *Cns_readdirg (Cns_DIR *);

ns/Cns_queryclass.c

@@ -17,7 +17,7 @@
 #include "serrno.h"
 
 int
-Cns_queryclass(char *server, int classid, char *class_name, struct Cns_fileclass *Cns_fileclass)
+Cns_queryclass(const char *server, int classid, const char *class_name, struct Cns_fileclass *Cns_fileclass)
 {
   int c;
   char func[16];

ns/Cns_queryclass.man

@@ -9,9 +9,9 @@ Cns_queryclass \- query about a fileclass definition in the name server
 .br
 \fB#include "Cns_api.h"\fR
 .sp
-.BI "int Cns_queryclass (char *" server ,
+.BI "int Cns_queryclass (const char *" server ,
 .BI "int " classid ,
-.BI "char *" class_name ,
+.BI "const char *" class_name ,
 .BI "struct Cns_fileclass *" Cns_fileclass )
 .SH DESCRIPTION
 .B Cns_queryclass