doc: hardware: peripherals: mipi_dbi: Added a newline to fix a typo

Added a newline to display the list correctly

The list is displayed like:
MIPI DBI defines 3 interface types: * Type A: Motorola 6800 parallel bus
 * Type B: Intel 8080 parallel bus

But it should be like:
MIPI DBI defines 3 interface types:
 * Type A: Motorola 6800 parallel bus
 * Type B: Intel 8080 parallel bus

This was fixed by an example from another doc:
doc/hardware/peripherals/i3c.rst

Signed-off-by: Dmytro Yaskov <dmytro.v.yaskov@gmail.com>