ranges/ptrlist: solve a leak with a big hack (second attempt)
The truth is that I don't know why the record_rl() way of freeing all the
rl ptr lists wasn't working. I really thought it should have worked.
Anyway, the new "fix" is to create a special ptr_list allocator for rl
pointer lists and then use the clear_ptrlist_alloc() to free it. It seems
to solve the issue I was having with running out of memory running
smatch --info on the kernel.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>