DataUsageSummary: fix mobile data usage display for sim-less devices

- Don't assume the device has a sim card. Check for a phone number
  instead. Otherwise the mobile data usage screen will not show up
  on sim-less CDMA devices.

Change-Id: Ic6e35dc209ff05e0c89dc990ad82f4ab4d3f337d
DataUsageSummary: fix mobile data usage display for GSM devices with no number

Some providers don't write phone number onto SIM card causing the
phone number check introduced in the partially reverted commit to fail.
Re-introduce the original check with the "or" condition.

This partially reverts commit 4c51b45355b9d6fed973f946738bf455a8b7c9ea.

Change-Id: I69a65a1a421dcdf168c3d0afeb7110cb97790034
Merge branch 'jb2' of git://github.com/CarbonDev/android_packages_apps_Settings into jb2