[FS#432] ath9k: Disconnections from WiFi (router as client)

[LEDE Bugs]

The following task has a new comment added:

FS#432 - ath9k: Disconnections from WiFi (router as client)
User who did this - ckdalsdk12 (ckdalsdk12)

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My Archer C7 v2 had same bug when 17.01-SNAPSHOT r3028 build.
But now, There is no bug when r3032 (after 36db143 commit) build.
2.4GHz radio still alive after 1 hour. It seems to have been fixed.
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=432#comment1457