Use a config struct instead of many arguments for display constructors

[dhalbert]

Some display constructors can take a lot of arguments:

• common_hal_rgbmatrix_rgbmatrix_construct() -- 15 args
• common_hal_busdisplay_busdisplay_construct() -- 28 args
• common_hal_epaperdisplay_epaperdisplay_construct() -- 35 (soon 36) args

Since C doesn't have default arg values or keywords args, the arg lists are quite unwieldy.

I propose creating a struct to pass to these constructors. The struct could be initialized with named fields, and many could be omitted if the default values are zero.