nterp: Load full class status in `ExecuteNterpWithClinitImpl`.

Loading an 8-bit chunk of a 32-bit field is a hack that we
do in compiled managed code to reduce code size because the
check is done very often. However, there is no good reason
to do that for `ExecuteNterpWithClinitImpl` just to save a
few bytes in `libart.so`.

Test: testrunner.py --host --interpreter
Test: testrunner.py --target --interpreter
Change-Id: Ibc0bec342e4981eac7170fe88226d06e85587b57