[Keymap] Add BB8520 trackpad support for CrKbd (#5925)

[Keymap] Add BB8520 trackpad support for CrKbd (#5925)

* Add vlukash CrKbd keymap to support trackpad adapter.

The trackpad adapter uses Elite-C board that has five extra pins.
Also SPI pins are taken for trackpad, keymap config updates column data
pins for matrix scan.

* Update vlukash keymap

* Enable pointing devide, configure mouse BTN1

* Set TAPPING_TERM to 300

* Add support for the BlackBerry 8520 trackpad

* Add vlukash keymap for master-right no-trackpad version

* Remap backspace

* Set EXTRAKEY_ENABLE = yes

* Update thumb keys mappings

* Set bootloader to atmel-dfu

* Sync keymap

* Add scrolling support

* Make debug LEDS conditional

* Add support for both flex and no-flex PCBs

* Add readme and rename root folders

* Update readme file with blog link

* Fix readme file formatting

* Remove ADJUST keycode, code cleanup.

* Add Win key to the keymap.