remove cmsync usage (cosmos#1151)

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## Overview

ref rollkit/rollkit#1125

remove usage of cmsync in rollkit 

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## Checklist

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- [ ] New and updated code has appropriate documentation
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---------

Co-authored-by: Marko Baricevic <[email protected]>

mempool/clist/clist.go

@@ -14,8 +14,6 @@ to ensure garbage collection of removed elements.
 import (
 	"fmt"
 	"sync"
-
-	cmsync "github.com/cometbft/cometbft/libs/sync"
 )
 
 // MaxLength is the max allowed number of elements a linked list is
@@ -42,7 +40,7 @@ and there's no reason to serialize that condition for goroutines
 waiting on NextWait() (since it's just a read operation).
 */
 type CElement struct {
-	mtx        cmsync.RWMutex
+	mtx        sync.RWMutex
 	prev       *CElement
 	prevWg     *sync.WaitGroup
 	prevWaitCh chan struct{}
@@ -218,7 +216,7 @@ func (e *CElement) SetRemoved() {
 // Operations are goroutine-safe.
 // Panics if length grows beyond the max.
 type CList struct {
-	mtx    cmsync.RWMutex
+	mtx    sync.RWMutex
 	wg     *sync.WaitGroup
 	waitCh chan struct{}
 	head   *CElement // first element

node/mempool.go

@@ -3,8 +3,8 @@ package node
 import (
 	"fmt"
 	"math"
+	"sync"
 
-	cmsync "github.com/cometbft/cometbft/libs/sync"
 	"github.com/libp2p/go-libp2p/core/peer"
 )
 
@@ -13,7 +13,7 @@ const (
 )
 
 type mempoolIDs struct {
-	mtx       cmsync.RWMutex
+	mtx       sync.RWMutex
 	peerMap   map[peer.ID]uint16
 	nextID    uint16              // assumes that a node will never have over 65536 active peers
 	activeIDs map[uint16]struct{} // used to check if a given peerID key is used, the value doesn't matter