Add a-ball handwired trackball based on ADSN9800 (#9015)

* Initial commit of kball

* Pretty much working

* Rename to aball

* Cleanup

* Fix typo and make instructions

* Refactor to use qmk spi

* Suggestions from ZVECR

* Update keyboards/handwired/aball/adns9800_srom_A6.h

* Update keyboards/handwired/aball/adns.c

* Update keyboards/handwired/aball/adns.c

* Update keyboards/handwired/aball/adns.c

* Added copyright and source attribution

* Update keyboards/handwired/aball/rules.mk

Include as quantum lib to help avoid timing issues with LTO

* Only send report on change, adj sensitivity, fix src include

* Fix issue causing constant reports and bad clamping

* Streamline conversion to int, add required wait before burst read

* Changes to track develop

* Update rules with new feature descriptors, add info.json

* Add stub layout

* Rework / cleanup key matrix.  Add missing CS pin define for new ADNS driver

* Add stub keymap to enable compile

keyboards/handwired/aball/rules.mk

@@ -0,0 +1,22 @@
+# MCU name
+MCU = atmega32u4
+
+# Bootloader selection
+BOOTLOADER = atmel-dfu
+
+# Build Options
+#   change yes to no to disable
+#
+BOOTMAGIC_ENABLE = no       # Enable Bootmagic Lite
+MOUSEKEY_ENABLE = yes       # Mouse keys
+EXTRAKEY_ENABLE = no        # Audio control and System control
+CONSOLE_ENABLE = no         # Console for debug
+COMMAND_ENABLE = no         # Commands for debug and configuration
+NKRO_ENABLE = no            # Enable N-Key Rollover
+BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality
+RGBLIGHT_ENABLE = no        # Enable keyboard RGB underglow
+AUDIO_ENABLE = no           # Audio output
+
+# Add trackball support
+POINTING_DEVICE_ENABLE = yes
+POINTING_DEVICE_DRIVER = adns9800