[Keymap] planck layout for kifinnsson (#8324)

[Keymap] planck layout for kifinnsson (#8324)

* [Keymap] kifinnsson keymap for planck

Initial commit for kifinnsson keymap
* placeholder macros
* extend layer

* [Keymap] kifinnsson planck keymap updates

commented out placeholder SEND_STRING macros

* Update keyboards/planck/keymaps/kifinnsson/keymap.c

Remove extern keymap_config_t keymap_config;

Co-Authored-By: James Young <18669334+noroadsleft@users.noreply.github.com>
* Update keyboards/planck/keymaps/kifinnsson/keymap.c

Changed KC_MENU to KC_APP

Co-Authored-By: James Young <18669334+noroadsleft@users.noreply.github.com>
* Removing COLEMAK set_single_persistent_default_layer

as suggested

Co-Authored-By: Drashna Jaelre <drashna@live.com>
* updated uinit32()_t to layer_state_t() for update_tri_layer_state

as suggested

Co-Authored-By: Drashna Jaelre <drashna@live.com>
* Removing COLEMAK keycode

Co-Authored-By: Drashna Jaelre <drashna@live.com>
* Removing COLEMAK keycode in _ADJUST layer

* Update keymap.c

added switch (keycode) back into process_record_user

Co-authored-by: Ki Finnsson <kifinnsson@wgu.edu>
Co-authored-by: James Young <18669334+noroadsleft@users.noreply.github.com>
Co-authored-by: Drashna Jaelre <drashna@live.com>