fix function and struct name

Signed-off-by: carrychair <linghuchong404@gmail.com>

promql/engine.go

@@ -1856,7 +1856,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 	panic(fmt.Errorf("unhandled expression of type: %T", expr))
 }
 
-// reuseOrGetFPointSlices reuses the space from previous slice to create new slice if the former has lots of room.
+// reuseOrGetHPointSlices reuses the space from previous slice to create new slice if the former has lots of room.
 // The previous slices capacity is adjusted so when it is re-used from the pool it doesn't overflow into the new one.
 func reuseOrGetHPointSlices(prevSS *Series, numSteps int) (r []HPoint) {
 	if prevSS != nil && cap(prevSS.Histograms)-2*len(prevSS.Histograms) > 0 {

tsdb/index/index.go

@@ -1829,7 +1829,7 @@ func NewStringListIter(s []string) StringIter {
 	return &stringListIter{l: s}
 }
 
-// symbolsIter implements StringIter.
+// stringListIter implements StringIter.
 type stringListIter struct {
 	l   []string
 	cur string