Refactor ExpectedSyms to return bool; document it

Document that we are looking for ANY of the expected symbols, and
simplify the code to return bool instead of an error.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

goscan.go

@@ -98,18 +98,13 @@ func readTable(fileName string) (*gosym.Table, error) {
 	return symTable, nil
 }
 
-// Checks the .gopclntab for the expected list of symbols.
-func ExpectedSyms(expectedSyms []string, symTable *gosym.Table) error {
-	found := false
+// Checks that .gopclntab contains any of the expectedSyms.
+func ExpectedSyms(expectedSyms []string, symTable *gosym.Table) bool {
 	for _, s := range expectedSyms {
 		fn := symTable.LookupFunc(s)
 		if fn != nil {
-			found = true
-			break
+			return true
 		}
 	}
-	if !found {
-		return fmt.Errorf("expected symbol(s) %v not found", expectedSyms)
-	}
-	return nil
+	return false
 }

validations.go

@@ -94,8 +94,8 @@ func validateGoSymbols(_ context.Context, _ *v1.TagReference, path string, baton
 		return nil
 	}
 
-	if err := ExpectedSyms(requiredGolangSymbols, symtable); err != nil {
-		return fmt.Errorf("go: expected symbols not found for %v: %w", filepath.Base(path), err)
+	if !ExpectedSyms(requiredGolangSymbols, symtable) {
+		return fmt.Errorf("go: expected symbols not found for %v", filepath.Base(path))
 	}
 	return nil
 }