fix a few function names on comments (#2496)

Signed-off-by: cui fliter <imcusg@gmail.com>

Signed-off-by: cui fliter <imcusg@gmail.com>

core/mr/mapreduce.go

@@ -145,7 +145,7 @@ func MapReduceChan(source <-chan interface{}, mapper MapperFunc, reducer Reducer
 	return mapReduceWithPanicChan(source, panicChan, mapper, reducer, opts...)
 }
 
-// MapReduceChan maps all elements from source, and reduce the output elements with given reducer.
+// mapReduceWithPanicChan maps all elements from source, and reduce the output elements with given reducer.
 func mapReduceWithPanicChan(source <-chan interface{}, panicChan *onceChan, mapper MapperFunc,
 	reducer ReducerFunc, opts ...Option) (interface{}, error) {
 	options := buildOptions(opts...)

tools/goctl/kube/kube.go

@@ -49,7 +49,7 @@ type Deployment struct {
 	ImagePullPolicy string
 }
 
-// DeploymentCommand is used to generate the kubernetes deployment yaml files.
+// deploymentCommand is used to generate the kubernetes deployment yaml files.
 func deploymentCommand(_ *cobra.Command, _ []string) error {
 	nodePort := varIntNodePort
 	home := varStringHome

tools/goctl/upgrade/upgrade.go

@@ -8,7 +8,7 @@ import (
 	"github.com/zeromicro/go-zero/tools/goctl/rpc/execx"
 )
 
-// Upgrade gets the latest goctl by
+// upgrade gets the latest goctl by
 // go install github.com/zeromicro/go-zero/tools/goctl@latest
 func upgrade(_ *cobra.Command, _ []string) error {
 	cmd := `GO111MODULE=on GOPROXY=https://goproxy.cn/,direct go install github.com/zeromicro/go-zero/tools/goctl@latest`