multimedia/flvmeta: Update to latest commit

Use latest commit as development seems to have slowed down upstream
and contains multiple build fixes

Changelog: https://github.com/noirotm/flvmeta/releases/tag/v1.2.2

Some addtional changes to patch:

• Use libyaml from ports instead of bundled version
• Use a pre-rendered man page instead of pulling in pandoc

PR: 259339
Approved by: maintainer timeout (1+ year)