Fix: compaction migratepages event name

Fix: compaction migratepages event name

The commit "fix: mm: compaction: fix the migration stats in trace_mm_compaction_migratepages() (v5.17)"

Triggers this warning:

    LTTng: event provider mismatch: The event name needs to start with provider name + _ + one or more letter, provider: compaction, event name: mm_compaction_migratepages

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I01c7485af765084dafb33bf33ae392e60bfbf1e7