Transceiver: Initialize mExtRACH in constructor

Doing so should make Coverity happy:
>>>     CID 200212:  Uninitialized members  (UNINIT_CTOR)
>>>     Non-static class member "mExtRACH" is not initialized in this constructor nor in any functions that it calls.

The current status is actually harmless since the field will be set
during init() time, and the variable is never used before init() is
called.

Fixes: Coverity CID#200212
Change-Id: I17286570a9a6db695a75147e5cbb18c9da7d0fe6
1 file changed