SchedSwitchHandler: rename private methods

SchedSwitchHandler: rename private methods

The setNewProcessPrio and setNewProcessExecName methods
were respectively renamed setProcessPrio and
setProcessExecName as the 'New' part of the name can be
confusing with the 'next process' when handling a
sched_switch event. The parameters of those methods have
been renamed accordingly.

Change-Id: Id1c0f00f165e2d906cb7650d511b1bebc20d4b1e
Signed-off-by: Raphaël Beamonte <raphael.beamonte@gmail.com>
Reviewed-on: https://git.eclipse.org/r/70514
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-by: Hudson CI
Reviewed-by: Alexandre Montplaisir <alexmonthy@efficios.com>
Tested-by: Alexandre Montplaisir <alexmonthy@efficios.com>