wifi: mt76: mt7921: refactor regd update to fix recursive mutex deadlock

Split mt7921_mcu_regd_update() into two functions to prevent recursive
mutex acquisition. Introduce __mt7921_mcu_regd_update() as the internal
implementation that assumes the mutex is already held by the caller,
while mt7921_mcu_regd_update() remains as the external interface that
handles mutex acquisition and release.

This fixes a deadlock issue when mt7921_regd_set_6ghz_power_type() is
called with the device mutex already held. Without this change, calling
mt7921_mcu_regd_update() would attempt to acquire the same mutex again,
causing a recursive lock deadlock.

The __mt7921_mcu_regd_update() function can be safely called when the
caller has already acquired the device mutex, avoiding the deadlock
while maintaining proper synchronization for regulatory domain updates.

Fixes: e88098133ed4 ("wifi: mt76: mt7921: refactor regulatory notifier flow")
Signed-off-by: Charlie-cy Wu <Charlie-cy.Wu@mediatek.com>
Link: https://patch.msgid.link/20260629083543.153564-1-jb.tsai@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>

0 files changed, 0 insertions, 0 deletions