snippets: nordic-log-stm: Do no enforce UART Asynchronous API

UART asynchronous API will ensure highest throughput but it is not
necessary as polling API is also supported as a fallback. Do not
enforce use of asynchronous API as there might be cases when polling
might be used (e.g. to reduce memory footprint).

Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>

snippets/nordic-log-stm-dict/boards/nrf54h20_cpuapp.conf

@@ -1 +0,0 @@
-CONFIG_UART_ASYNC_API=y

snippets/nordic-log-stm-dict/snippet.yml

@@ -5,7 +5,6 @@ boards:
   /.*/nrf54h20/cpuapp/:
     append:
       EXTRA_DTC_OVERLAY_FILE: boards/nrf54h20_cpuapp.overlay
-      EXTRA_CONF_FILE: boards/nrf54h20_cpuapp.conf
   /.*/nrf54h20/cpurad/:
     append:
       EXTRA_DTC_OVERLAY_FILE: boards/nrf54h20_cpurad.overlay

snippets/nordic-log-stm/boards/nrf54h20_cpuapp.conf

@@ -1 +0,0 @@
-CONFIG_UART_ASYNC_API=y

snippets/nordic-log-stm/snippet.yml

@@ -5,7 +5,6 @@ boards:
   /.*/nrf54h20/cpuapp/:
     append:
       EXTRA_DTC_OVERLAY_FILE: boards/nrf54h20_cpuapp.overlay
-      EXTRA_CONF_FILE: boards/nrf54h20_cpuapp.conf
   /.*/nrf54h20/cpurad/:
     append:
       EXTRA_DTC_OVERLAY_FILE: boards/nrf54h20_cpurad.overlay