Treat data in service as camped

Problem:
android.telephony.sdk28.cts.CellInfoTest#testCellInfoSdk28 fails on LTE only devices
Initial condition:
1. LTE only devices
2. Download GSI image
Root cause:
LTE only device with GSI, device will not register on VOLTE, and CS will not in service.
But in testCellInfoSdk28, only voice state is checked in isCamped(), it makes case fail.
Solution:
Treat data in service as camped

Test: android.telephony.sdk28.cts.CellInfoTest#testCellInfoSdk28 can pass

Bug: 195364974
(cherry picked from commit d41aa2815f19f52350ba4a867dd959344c8b2d1a)

Change-Id: If940c47af9b8e28a4269f736e4f0e655cc2fd495
Merged-In: I793ac8b2d9456e916ab8945f780d06be2101d163