In most cases, it copies the entire strv needlessly.
We can do better.

Also, the max_tokens argument is handled wrongly (albeit
not used anywhere anymore).

nmc_strsplit_set() handles max_token wrong. It cannot call
g_strsplit_set() with max_token first, and then split empty
words. You cannot use g_strsplit_set() to achieve what
nmc_strsplit_set() wants to do, unless you first split all
tokens, then them construct them together again -- thereby
loosing the delimiters.

Anyway, there are just a few caller that do essentially the same.

Refactor the code to not use nmc_strsplit_set().

nmc_strsplit_set()'s max_token argument is broken,
because it *first* calls g_strsplit_set() and then removes
empty tokens. It wasn't an issue, because DEFINE_SETTER_PRIV_KEY()
would first already remove leading spaces, and who uses multiple
spaces anyway...

Anyway, refactor DEFINE_SETTER_PRIV_KEY() to not use it.

nmcli calls nm_setting_802_1x_set_private_key() with a password pointer that
it just got from the setting connection itself. Make this less fragile, by
not freeing the current password before assigning it.

There are a few cases where we don't want to clear a potential
nm-generated/volatile flag, but only mark the connection as
unsaved.

Otherwise, we wrongly end up clearing these flags and the connection
is wrongly not NM_DEVICE_SYS_IFACE_STATE_EXTERNAL.

Fixes: 35dc6421de78cffd1761cfb6edf9e94233f99966

https://bugzilla.gnome.org/show_bug.cgi?id=790630

Format:

  QDISC1=ingress
  QDISC2="root handle 1234: fq_codel"
  FILTER1="parent ffff: matchall action simple sdata Input"
  FILTER2="parent 1234: matchall action simple sdata Output"

Also add a define NM_PLATFORM_ACTION_KIND_SIMPLE. It makes the
uses of "simple" grepable.