powerpc/fsl: Use new clockgen binding

The driver retains compatibility with old device trees, but we don't
want the old nodes lying around to be copied, or used as a reference
(some of the mux options are incorrect), or even just being clutter.

Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Tang Yuantian <andy.tang@nxp.com>
[scottwood: removed sysclk node added by Andy]
Signed-off-by: Scott Wood <oss@buserror.net>

powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes

This allows new-style clock references to be used, which is needed for
fman. The old clock nodes will be removed and all clock references
converted to new-style once the qoriq-cpufreq driver is updated to stop
depending on the old-style references in cpu nodes.

Signed-off-by: Scott Wood <scottwood@freescale.com>

powerpc/dts: Add node(s) for the platform PLL

Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Change-Id: If76cd705a01813abe53396c1486bc13c4289ee92
Signed-off-by: Scott Wood <scottwood@freescale.com>

powerpc/dts: Factorize the clock control node

Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com>
Change-Id: I25ce24a25862b4ca460164159867abefe00ccdd1
Signed-off-by: Scott Wood <scottwood@freescale.com>