build: fix valgrind support
build: fix valgrind support

no need to call tests with libtool, because they are linked with
-no-install, disabling libtool wrappers.

also, removed glib-related environment variables, that aren't needed
here.

rafaelmartins/blogc,rafaelmartins/blogc,rafaelmartins/blogc,blogc/blogc,blogc/blogc,blogc/blogc