Battery: fix the battery status when some battery devices are not valid

It happens that some devices are considered as batteries, even if they
cannot be charged or used as a power supply for the laptop.
The ELAN device deals with the touchpad and is a "battery". When looking
at the udev info, it appears that there is no technology present as
well as the basic battery info (energy levels).

P: /devices/pci0000:00/0000:00:15.0/i2c_designware.0/i2c-0/i2c-ELAN24CC:00/0018:04F3:24CC.0003/power_supply/hid-0018:04F3:24CC.0003-battery
E: DEVPATH=/devices/pci0000:00/0000:00:15.0/i2c_designware.0/i2c-0/i2c-ELAN24CC:00/0018:04F3:24CC.0003/power_supply/hid-0018:04F3:24CC.0003-battery
E: POWER_SUPPLY_CAPACITY=1
E: POWER_SUPPLY_MODEL_NAME=ELAN24CC:00 04F3:24CC
E: POWER_SUPPLY_NAME=hid-0018:04F3:24CC.0003-battery
E: POWER_SUPPLY_ONLINE=1
E: POWER_SUPPLY_PRESENT=1
E: POWER_SUPPLY_SCOPE=Device
E: POWER_SUPPLY_STATUS=Discharging
E: SUBSYSTEM=power_supply

The issue with that kind of devices is that it confuses the battery
gadget. Since two batteries are present, the total capacity is divided
by 2, resulting in the gadget displaying only 50% when the battery is
fully charged.
To avoid this, we check that the battery technology is known.

@fix

src/modules/battery/e_mod_main.c

@@ -299,7 +299,7 @@ _battery_device_update(void)
 
    EINA_LIST_FOREACH(device_batteries, l, bat)
      {
-        if (!bat->got_prop)
+        if ((!bat->got_prop) || (!bat->technology))
           continue;
         have_battery = 1;
         batnum++;