Put XPDEV_MT_LIBS after CRYPT_LIBS (fixes centos build)

Since on 2.17, pthread_afork() is not in libc, -lpthread must be
after -lcl (library link order issue)

Fixes #211

BIG thanks to Scott Comstock for giving me access to his box to fix
this.

src/sbbs3/scfg/GNUmakefile

@@ -8,4 +8,4 @@ vpath %.c ..
 
 $(SCFG): $(OBJS) $(CRYPT_DEPS)
 	@echo Linking $@
-	${QUIET}$(CC) $(LDFLAGS) $(MT_LDFLAGS) -o$@ $(OBJS) $(SMBLIB_LIBS) $(ENCODE_LIBS) $(HASH_LIBS) $(UIFC-MT_LIBS) $(CIOLIB-MT_LIBS) $(XPDEV-MT_LIBS) $(CRYPT_LIBS)
+	${QUIET}$(CC) $(LDFLAGS) $(MT_LDFLAGS) -o$@ $(OBJS) $(SMBLIB_LIBS) $(ENCODE_LIBS) $(HASH_LIBS) $(UIFC-MT_LIBS) $(CIOLIB-MT_LIBS) $(CRYPT_LIBS) $(XPDEV-MT_LIBS)