Revert "SystemUI: Fix mobile data connection type hiding"

This reverts commit b2aac59c.

This is intentional and is only displayed when 2 connections
are connected at the same time.

E.g.  If you're connected to Wi-Fi with a captive portal, then
3G will remain connected and normal data connectivity will go
through 3G until you have logged in via Wi-Fi.

In that case, the correct display is Wi-Fi with "!" and mobile
with "3G".

Change-Id: I985c361a656d15b145e467542508dcef41f92df5