[nrf fromtree] tests/flash/common: Add nrf54l15pdk to list of allowed platforms

Allows running tests on nrf54l15pdk/nrf54l15/cpuapp.

Signed-off-by: Dominik Ermel <[email protected]>
(cherry picked from commit 12bfefd)

Author: de-nordic

tests/drivers/flash/common/testcase.yaml

@@ -35,6 +35,9 @@ tests:
     integration_platforms:
       - qemu_x86
       - mimxrt1060_evk
+  drivers.flash.common.no_explicit_erase:
+    platform_allow:
+      - nrf54l15pdk/nrf54l15/cpuapp
   drivers.flash.common.tfm_ns:
     build_only: true
     filter: (CONFIG_FLASH_HAS_DRIVER_ENABLED and CONFIG_TRUSTED_EXECUTION_NONSECURE