testing: Don't run tests when building tkm-rpc

There are issues with some versions of the XML/Ada library on i386,
blocking the build of the testing environment when these tests are run.
TKM tests won't work in such a case but at least make-testing does not
block with this patch.

Fixes #336.

testing/scripts/recipes/006_tkm-rpc.mk

@@ -16,7 +16,7 @@ all: install
 	@touch $@
 
 .$(PKG)-built: .$(PKG)-cloned
-	cd $(PKG) && make tests && make
+	cd $(PKG) && make
 	@touch $@
 
 install: .$(PKG)-built