perf testsuite: Add initialization script for shell tests

Initialize reporting and logging functions that unifies formatting
of the test output used for shell tests.

Signed-off-by: Veronika Molnarova <vmolnaro@redhat.com>
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Cc: kjain@linux.ibm.com
Cc: atrajeev@linux.vnet.ibm.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240215110231.15385-4-mpetlan@redhat.com