update gssapi/ntlm for windows build

NTMakefile:
  replace ntlm/inquire_cred.c with ntlm/creds.c
  add ntlm/inquire_sec_context_by_oid.c
  add ntlm/iter_cred.c

add missing GSSAPI_CALLCONV function descriptors

conditionalize use of kcm functions with HAVE_KCM

Change-Id: Ia693f67304405bd540c57db8858c13314cd60322

lib/gssapi/ntlm/iter_cred.c

@@ -35,11 +35,12 @@
 
 #include "ntlm.h"
 
-void
+void GSSAPI_CALLCONV
 _gss_ntlm_iter_creds_f(OM_uint32 flags,
 		       void *userctx ,
 		       void (*cred_iter)(void *, gss_OID, gss_cred_id_t))
 {
+#ifdef HAVE_KCM
     krb5_error_code ret;
     krb5_context context = NULL;
     krb5_storage *request, *response;
@@ -93,5 +94,6 @@ _gss_ntlm_iter_creds_f(OM_uint32 flags,
  done:
     if (context)
 	krb5_free_context(context);
+#endif /* HAVE_KCM */
     (*cred_iter)(userctx, NULL, NULL);
 }