codeowners: Add missing entry for nRF70 external flash module

This was missed in the original commit.

Signed-off-by: Chaitanya Tata <[email protected]>

Author: krish2718

CODEOWNERS

@@ -681,6 +681,7 @@
 /subsys/net/lib/hostap_crypto/            @krish2718 @jukkar @vivekuppunda
 /subsys/net/lib/icalendar_parser/         @lats1980
 /subsys/net/lib/lwm2m_client_utils/       @nrfconnect/ncs-co-networking @nrfconnect/ncs-iot-oulu
+/subsys/net/lib/nrf70_fw_ext/             @krish2718 @sachinthegreen
 /subsys/net/lib/nrf_cloud/                @nrfconnect/ncs-nrf-cloud
 /subsys/net/lib/nrf_provisioning/         @nrfconnect/ncs-iot-oulu
 /subsys/net/lib/zzhc/                     @junqingzou