Samsung STK: Add USSD support

Allow USSD-based STK applications to work

Change-Id: I483f37a44a6c3ed43eefcf979e17b84877d03f93

Conflicts:
	src/java/com/android/internal/telephony/cat/CatService.java
Samsung STK: Fix SMS-based STK

SEND_SMS was falling through to SEND_USSD (which used to do nothing
until USSD support was added) causing an Exception because cmdParams
is not an instance of SendUSSDParams.

Fix by using type-checking instead of checking if Samsung STK is
enabled (because SendSMSParams and SendUSSDParams will only be
created if Samsung STK is enabled.)

Change-Id: I671014e295e9e529aad25a8b6fbd5a2e5788fc44
Fix Samsung STK code for msim

Change-Id: I726f03351f42ce58b8387fad20adfac224c28199

Conflicts:
	src/java/com/android/internal/telephony/cat/CatService.java