apparmor: add support for 2^24 states to the dfa state machine.

Currently the dfa state machine is limited by its default, next, and
check tables using u16. Allow loading of u32 tables, and if u16 tables
are loaded map them to u32.

The number of states allowed does not increase to 2^32 because the
base table uses the top 8 bits of its u32 for flags. Moving the flags
into a separate table allowing a full 2^32 bit range wil be done in
a separate patch.

Link: https://gitlab.com/apparmor/apparmor/-/issues/419


Signed-off-by: John Johansen <john.johansen@canonical.com>