Fix ART crash during initialization.

The CDMAPhone has a static member that initializes a regexp pattern.
Unfortunately the java.util.regex.Pattern class is not allowed to be called
during ART bootstrap process which causes a bootloop.

To fix this the initialization has been moved into the only method that
uses this regular expression.

Change-Id: I25519cb5b6aa0eb4586eed2bdcd631e1dba24376