Change in coreboot[master]: mb/google/dedede/var/galith: support Audio AMP I2C/Auto mode

[Karthik Ramasubramanian (Code Review)]

Attention is currently required from: Henry Sun, Frank Chu.
Karthik Ramasubramanian has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52286 )

Change subject: mb/google/dedede/var/galith: support Audio AMP I2C/Auto mode
......................................................................

Patch Set 2:

(3 comments)

File src/mainboard/google/dedede/variants/baseboard/devicetree.cb:

https://review.coreboot.org/c/coreboot/+/52286/comment/6a5cbb8b_37db914d 
PS2, Line 13: 	field AUDIO_AMP 14 16
            : 		option UNPROVISIONED 0
            : 		option MAX98360 1
            : 		option RT1015_I2C 2
            : 		option RT1015P_AUTO 3
            : 	end
Prefer to keep this baseboard change in a separate CL.

File src/mainboard/google/dedede/variants/galtic/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/52286/comment/2460c32b_b1bbd55a 
PS2, Line 171: 					probe AUDIO_AMP RT1015_I2C
probe AUDIO_AMP_RT1015_I2C | UNPROVISIONED

https://review.coreboot.org/c/coreboot/+/52286/comment/bc398571_57671805 
PS2, Line 179: 					probe AUDIO_AMP RT1015_I2C
Same comment as above.