append changelog to fulfill the license obligation

[SilverSteven]

Reminding about missing "notices" for modifications on original work (violation of GPL-2.0)

Hello,

[Modification terms and conditions in license] The original work should be honored while the modifications on it should be attached with prominent notices as the license GPL-2.0 dictates. Your project is a forking project from citra-emu/citra which adopts GPL-2.0 as its project license.
The modification terms and conditions of GPL-2.0 dictate that:

GPL-2.0:

... You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change. ...

Therefore, we think the project is obligated to abide by the modification terms and conditions in GPL-2.0.

[Violation of modification terms and conditions] We run through your history, and it turns out that you have conducted modifications to the source files of original work while didn't provide prominent notices.
You have 98 commits which conduct modifications to the files of original work, all of which are not declared in README.md.
According to the license terms and conditions above, it is regarded as license violation.
Thus, to avoid potential legal risks, I would suggest you carry out prominent notices for the 98 commits.

[Recommended Fix] There are 2 recommended solutions to fulfill the modification related obligation of GPL-2.0:

1. Git Mechanism.

   • Put a note in the top directory, something like MODIFICATION.md, or any file but the license text and NOTICES, in order to give people who follow you the most latitude to comply with the license without making a mess,
   • Write "In compliance with the GPL-2.0 license: I declare that this version of the program contains my modifications, which can be seen through the usual "git" mechanism."

2. Changelog Text.
   Add changelog for modification to comply with the license.

For your convenience, I created a PR with by picking up modification-related commit messages. It adds a few lines in changelog without touching the codebase. Please be comfortable to check it out.

Full details of the report you could refer to the html file attached.
Hope it helps!

Cheers!