SamsungQualcommRIL: Add more validation of Signal Strength

Change-Id: I4b166543ba6898616c9e64a86ff65693f8e33f72
SamsungQualcommRil: reversed engineered implimentation of dial() from touchwiz

derived from Ricardo Ceq. and Tony Layher work.

Change-Id: Ie17762a5bce84791f85c98dfca88f576b2f5aeb9