Flipping NR signal strengths coming from HAL

The documentation of NrSignalStrength states that some
of the cell signal strength values should be flipped when
taken in from the HAL (this matches what LTE does.)  The
current implementation did not match this behavior, this
chagne fixes that.

Bug: 144667130
Test: FrameworkTests
Change-Id: Ica2595c5b6480a52209fe5ec93de63c9f323316a