PIN/PUK: support to get default PIN/PUK remaining count

It is a new mechanism to pass an empty PIN/PUK code to explicitly
request the number of PIN/PUK retries.

After removal of exception null check, Although RIL returns SUCCESS
with retries, which in this situation ATEL does not cause exception,
ATEL can still parse and get default PIN/PUK remaining count.

CRs-Fixed: 628782

Change-Id: If1855e691f61fa636b42a225b15c387c01134438