[media] media: davinci: vpss: enable vpss clocks

By default the VPSS clocks were enabled in capture driver
for davinci family which creates duplicates for dm355/dm365/dm644x.
This patch adds support to enable the VPSS clocks in VPSS driver,
which avoids duplication of code and also adding clock aliases.
This patch uses PM runtime API to enable/disable clock, instead
of DaVinci clock framework. con_ids for master and slave clocks of
vpss is added in pm_domain.
This patch cleanups the VPSS clock enabling in the capture driver,
and also removes the clock alias in machine file. Along side adds
a vpss slave clock for DM365 as mentioned by Sekhar
(https://patchwork.kernel.org/patch/1221261/

).
The Suspend/Resume in dm644x_ccdc.c which enabled/disabled the VPSS clock
is now implemented as part of the VPSS driver.

Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>