apparmor: replace recursive profile removal with iterative approach

In the Linux kernel, the following vulnerability has been resolved:

apparmor: replace recursive profile removal with iterative approach

The profile removal code uses recursion when removing nested profiles,

which can lead to kernel stack exhaustion and system crashes.

Reproducer:

$ pf='a'; for ((i=0; i<1024; i++)); do

echo -e "profile $pf { \n }" | apparmor_parser -K -a;

pf="$pf//x";

done

$ echo -n a > /sys/kernel/security/apparmor/.remove

Replace the recursive __aa_profile_list_release() approach with an

iterative approach in __remove_profile(). The function repeatedly

finds and removes leaf profiles until the entire subtree is removed,

maintaining the same removal semantic without recursion.