coresight/etm3/4x: Consolidate hotplug state space

Even if both drivers are compiled in only one instance can run on a given
system depending on the available tracer cell.

So having seperate hotplug states for them is pointless.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: http://lkml.kernel.org/r/20161221192112.162765484@linutronix.de


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>