samples: qmi: Use the unified QMI service ID instead of defining it locally

samples: qmi: Use the unified QMI service ID instead of defining it locally

Instead of defining a local macro with a custom name for the QMI
service identifier, use the one provided in qmi.h and remove the
locally defined macro.

Signed-off-by: Daniel Lezcano <daniel.lezcano@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260309230346.3584252-9-daniel.lezcano@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>