EF_SDN and EF_EXT3 under DF_ADF shall be selected for USIM application

Service dial number shall be retrieved from EF_SDN and EF_EXT3 under
DF_ADF if USIM application is active.

UsimFileHandler.getEFPath() returns MF_SIM + DF_ADF for EF_FDN and
EF_EXT2 in the current implementation. EF_SDN and EF_EXT3 shall also be
treated in the same way.

Bug: 30330927
Change-Id: I7282c5d1ab30369f7e967ececd53905de67d5ad9