SJCAM SJ8 Pro: add missing gamma tables

[RigacciOrg]

The configuration file config-SJ8-SJ9/gamma.json only refers to some firmware files:

• adj_video_default_00_Imx377
• adj_video_default_01_Imx377
• adj_video_default_02_Imx377
• adj_video_default_03_Imx377
• adj_still_default_00_Imx377

but firmware contains also the following:

• adj_video_default_04_Imx377
• adj_video_default_05_Imx377
• adj_hiso_still_default_00_Imx377

The structure of the files (offsets, etc.) is the same of the existing ones (beware that _video_ files differs from _still_ ones).

I discovered that:

• adj_video_default_04_Imx377 is used for 720@240 video mode
• adj_video_default_05_Imx377 is used for 4K@(25,30) video modes, when Gyro Stabilizer is enabled.
• adj_hiso_still_default_00_Imx377 is used for photo and photo lapse when ISO mode is 800,1600,3200,6400

Please, refer to the complete table I wrote here: What gamma curves are applied on each video mode.

Here it is a completed gamma.json, which I'm using happily.