[mythtv-cmyth] Release v1.6.10

Hi Lars,

this updates the MythTV Frodo addon to version 1.6.10.

The most noticeable issue resolved is that the recording list didn't get updated anymore for people living in an area with DST. Therefore I hope this can make it to the 12.2 maintenance release.

Thanks,
Christian

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- Fixed crash when setting up Live TV (in rare cases)
- Fixed issue with not updated recording list (Daylight Saving Time)
- Fixed issue with empty recording list (caused by '[' character)
- Fixed playback of recordings made by a slave backend
- Removed 'Failed to connect to MythTV Backend' notification 

+ Some changes under the hood (improve data buffers and mutexes). This does not have any functional impacts, but cleans up some code parts, and might improve performance under certain conditions.