modules: lvgl: Remove Kconfig symbols that dont exist
modules: lvgl: Remove Kconfig symbols that dont exist

LV_Z_DISPLAY_DEV_NAME, LV_Z_HOR_RES_MAX, & LV_Z_VER_RES_MAX
Kconfig symbols don't exist anymore.  They got removed in
recent devicetree update of lvgl module.  So remove them from
modules/Kconfig.lvgl.

Signed-off-by: Kumar Gala <383ef5577c6e1178b93f59ec8d0936f76d2a98c4@kernel.org>

galak/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr