wifi: esp_at: claim net_context in rx
wifi: esp_at: claim net_context in rx

Claim the net_context mutext associated with a socket before claiming
the socket mutex. The receive callback claims the net_context mutex
internally, which will now always succeed immediately.

The TX path claims the net_context mutex before the socket mutex, and if
we don't use the same order, we can end up in a deadlock.

Fixes #43470.

Signed-off-by: Jordan Yates <d74a90e280bbad1cc3646781a4e234b467b60fe1@data61.csiro.au>

galak/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr