fix(event): enable ksymbols engine for PrintMemDump (#3443)

Commit 1a47a4e attempted to fix this issue by reverting some changes
made during the event definitions (and dependencies) refactor. That
change caused some regressions because of another fix made together,
but, since it was reverted, this commit fixes the same issue with a much
simpler approach (at least until the event definitions refactor work is
finished).

Fixes: #3382

pkg/events/core.go

@@ -10344,7 +10344,13 @@ var CoreEvents = map[ID]Definition{
 			ids: []ID{
 				DoInitModule,
 			},
-			kSymbols: []KSymbol{},
+			kSymbols: []KSymbol{
+				// Special case for this event: Single symbol, common to all kernel versions. Placed
+				// here so the ksymbols engine is always enabled, during tracee startup. The symbols
+				// are resolved dynamically, during runtime depending on the arguments passed to
+				// the event.
+				{symbol: "_stext", required: true},
+			},
 			capabilities: Capabilities{
 				base: []cap.Value{
 					cap.SYSLOG, // read /proc/kallsyms