power/polaris: Replace ops and batsem with dev

and remove the batsem initialization since it is arleady done in common code

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I6561eb53f3211edae8f699fbf9d7625689ee581c

drivers/power/polaris.c

@@ -139,8 +139,7 @@ struct stwlc38_dev_s
 {
   /* The common part of the battery driver visible to the upper-half driver */
 
-  FAR const struct battery_charger_operations_s *ops; /* Battery operations */
-  sem_t batsem;                                       /* Enforce mutually exclusive access */
+  struct battery_charger_dev_s dev; /* Battery charger device */
 
   /* Data fields specific to the lower half STWLC38 driver follow */
 
@@ -763,8 +762,7 @@ FAR struct battery_charger_dev_s *
     {
       /* Initialize the SC8551 device structure */
 
-      nxsem_init(&priv->batsem, 0, 1);
-      priv->ops       = &g_stwlc38ops;
+      priv->dev.ops   = &g_stwlc38ops;
       priv->i2c       = i2c;
       priv->addr      = addr;
       priv->frequency = frequency;