radix tree test suite: Fix split/join memory leaks

The last of the memory leaks in the test suite was a couple of places in
the split/join testing where I forgot to free the element being removed
from the tree.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Rehas Sachdeva <aquannie@gmail.com>
1 file changed