replace delay with sleep per kernel doc recomendations

reform2-lpc-driver/src/reform2-lpc.c

@@ -55,10 +55,11 @@ static struct power_supply_desc bat_desc = {
     .type = POWER_SUPPLY_TYPE_BATTERY,
 };
 
+static struct power_supply_config psy_cfg = {};
+
 static int lpcProbe(struct spi_device *spi)
 {
     struct lpc_driver_data *data;
-    struct power_supply_config psy_cfg = {};
     int ret;
 
     printk(KERN_INFO "%s: probing ...\n", "reform2-lpc");
@@ -274,16 +275,14 @@ static ssize_t lpcCommand(struct device *dev, char command, uint8_t arg1, uint8_
     {
         printk(KERN_INFO "%s: spi_write failed\n", __func__);
     }
-    // todo, replace with wait timer?
-    mdelay(70);
+    msleep(50);
 
     ret = spi_read(data->spi, responseBuffer, 8);
     if (ret)
     {
         printk(KERN_INFO "%s: spi_read failed\n", __func__);
     }
-    // todo, replace with wait timer?
-    mdelay(70);
+    msleep(50);
     mutex_unlock(&data->lock);
 
     return ret;