Update DeviceType to fix json parse error: unknown variant `STB`

[dzubybb]

Description

Fix json parse error: unknown variant STB when calling device() method.

Motivation and Context

Fixes #383

Type of change

Please delete options that are not relevant.

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How has this been tested?

I have device with Stb type, calling device() method from spotifyd returns error above. Adding lines from this pull request fixes the error.

Is this change properly documented?

No changes in documentation were made.

[ramsayleung]

@dzubybb Thanks for your contribution, would you like to update the CHANGELOG.md to include this modification :)

[dzubybb]

@dzubybb Thanks for your contribution, would you like to update the CHANGELOG.md to include this modification :)

No problemo, done :)