samples: zephyr: drivers: audio: dmic: Disable on nrf54lm20pdk

Original sample in the Zephyr repository is now executed on
final board name of nrf54lm20dk/nrf54lm20a/cpuapp.

Disable execution on obsolete nrf54lm20pdk target.

Signed-off-by: Sebastian Głąb <[email protected]>

Author: nordic-segl

samples/zephyr/drivers/audio/dmic/boards/nrf54lm20pdk_nrf54lm20a_cpuapp.overlay

@@ -13,13 +13,4 @@ tests:
       regex:
         - "DMIC sample"
         - "Exiting"
-    platform_allow:
-      - nrf54lm20pdk/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
-    integration_platforms:
-      - nrf54lm20pdk/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
-      - [email protected]/nrf54lm20a/cpuapp
+    depends_on: future_target