Fix HP_OUT in standalone association selected as default output when disconnected

[rdmitry0911]

Summary

On codecs where the headphone pin is in its own association (hpredir=-1, e.g. ALC897 on Gigabyte Z390 AORUS MASTER), switchHandler previously skipped it entirely. This left HPHN_ENABLE set in the pin control register regardless of whether headphones are physically present. macOS interprets HPHN_ENABLE as "headphones connected" and selects that PCM device as the default output on every reboot — even when no headphones are plugged in.

Root cause (from user dump analysis)

• Codec: Realtek ALC897 (0x10ec0897)
• NID 27 (Headphones, front panel): as=7, hpredir=-1 — standalone association, skipped by existing switchHandler loop
• NID 20 (External Speaker): as=1, separate association
• At init, NID 27 gets pin ctrl = 0xC0 (HPHN_ENABLE | OUT_ENABLE) unconditionally → macOS selects Headphones as default output

Fix

Add a second loop in switchHandler that processes HP_OUT pins in standalone associations (hpredir < 0):

• Reads actual presence detection from hardware
• Clears HPHN_ENABLE when no headphones are inserted → macOS does not see headphones and keeps External Speaker as default
• Sets HPHN_ENABLE when headphones are present, and calls hpSwitchHandler to mute/unmute other output associations (e.g. external speakers)
• Applied to both tranc and branches/zdev

Test plan

• Boot without headphones connected → External Speaker remains the default output
• Reboot without headphones → External Speaker still selected, no regression
• Plug in headphones → Headphones become active, External Speaker muted
• Unplug headphones → External Speaker restored
• Boot with headphones connected → Headphones selected as default

🤖 Generated with Claude Code