msm7x30: Support UICC hotswap.

Although this is almost impossible in hardware, the software supports it. It's
currently needed because before radio power on, SIM is reported as absent.

Conflicts:
	overlay/frameworks/base/core/res/res/values/config.xml

Change-Id: Ic3bff589f08da4942d1a3fc7415a8974b4363811