edid support digital input types

[kallisti5]

Our EDID headers are designed as follows:

​https://git.haiku-os.org/haiku/tree/headers/private/graphics/common/edid_raw.h

// display info
typedef struct _PACKED {
        BBITFIELD8_7 (
                input_type : 1,         // 1 : digital
                input_voltage : 2,      // 0=0.7V/0.3V, 1=0.714V/0.286, 
                                                        // 2=1V/0.4V, 3=0.7V/0V
                setup : 1,                      // true if voltage configurable
                sep_sync : 1,
                comp_sync : 1,
                sync_on_green : 1,
                sync_serr : 1
        );

However, per the EDID (1.4) specifications, when input_type changes from 0 (analog) to 1 (digital), the meaning of the bits of the first bitfield change. (see attached screenshot)

We should likely rename these "input_settings : 7", and parse them manually in our code when we translate from edid1_display_raw to edid1_display.

[kallisti5]

source: ​https://en.wikipedia.org/wiki/Extended_Display_Identification_Data

[kallisti5]

edid spec

[kallisti5]

x512 suggested a union. I agree and made ​https://review.haiku-os.org/c/haiku/+/4775.

The reason for this one is the radeon_hd driver wants to know the bits_per_color edid field for AtomBIOS + deep color.

[kallisti5]

results for gerrit review

[pulkomandy]

Merged in hrev55740.