toolchain: Fix libthreaddb not being installed

Signed-off-by: Michel Stam <m.stam@fugro.nl>

SVN-Revision: 42752

package/libs/toolchain/Makefile

@@ -508,7 +508,7 @@ ifeq ($(CONFIG_EXTERNAL_TOOLCHAIN),)
 	$(INSTALL_DIR) $(1)/lib
 	$(CP) \
 		$(TOOLCHAIN_DIR)/lib/libthread_db.so.* $(1)/lib
-  ifeq ($(USE_UCLIBC),y)
+  ifeq ($(CONFIG_USE_UCLIBC),y)
 	$(CP) \
 		$(TOOLCHAIN_DIR)/lib/libthread_db-$(LIBC_SO_VERSION).so \
 		$(1)/lib/