s390/cpumf: remove raw event support in basic-only sampling mode

Raw sample was implemented to export the diagnostic samples.
With having this achieved with AUX buffers, there is no requirement
for basic samples to export raw data.  In particular, most basic
sampling information are consumed for creating the perf event sample.

Signed-off-by: Pu Hou <bjhoupu@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>