Telephony[MSIM]: Change the package name of NumPadKey.

NumPadKey is moved to package "com.android.keyguard".

Change the package name from
"com.android.internal.policy.impl.keyguard.NumPadKey" to
"com.android.keyguard" in layout file.

Change-Id: Id8ec2a5b58b5c0e8bf153e5160091d2a30dedce6
CRs-Fixed: 588162