clk: meson: vid-pll-div: remove warning and return 0 on invalid config

The vid_pll_div is a programmable fractional divider, but vendor gives a
limited of known configuration value and it's corresponding fraction.

Thus when at reset value (0) or unknown value, we cannot determine the
result rate.

The initial behaviour was to print a warning, but the warning triggers
at each boot and when the clock tree is refreshed.

This patch moves the print to debug and returns 0 instead of the
parent rate.

Fixes: 72dbb8c94d0d ("clk: meson: Add vid_pll divider driver")
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lkml.kernel.org/r/20190327151348.27402-1-narmstrong@baylibre.com

clk: meson: rework and clean drivers dependencies

Initially, the meson clock directory only hosted 2 controllers drivers,
for meson8 and gxbb. At the time, both used the same set of clock drivers
so managing the dependencies was not a big concern.

Since this ancient time, entropy did its job, controllers with different
requirement and specific clock drivers have been added. Unfortunately, we
did not do a great job at managing the dependencies between the
controllers and the different clock drivers. Some drivers, such as
clk-phase or vid-pll-div, are compiled even if they are useless on the
target (meson8). As we are adding new controllers, we need to be able to
pick a driver w/o pulling the whole thing.

The patch aims to clean things up by:
* providing a dedicated CONFIG_ for each clock drivers
* allowing clock drivers to be compiled as a modules, if possible
* stating explicitly which drivers are required by each controller.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20190201125841.26785-5-jbrunet@baylibre.com

clk: meson: Mark some things static

These are missing 'static' so sparse complains:

drivers/clk/meson/vid-pll-div.c:58:26: warning: symbol '_get_table_val' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1585:12: warning: symbol 'gxbb_vid_pll_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1620:12: warning: symbol 'gxbb_vclk_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:1980:12: warning: symbol 'gxbb_cts_parent_names' was not declared. Should it be static?
drivers/clk/meson/gxbb.c:2036:12: warning: symbol 'gxbb_cts_hdmi_tx_parent_names' was not declared. Should it be static?

Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: meson: Add vid_pll divider driver

Add support the VID_PLL fully programmable divider used right after the
HDMI PLL clock source. It is used to achieve complex fractional division
with a programmble bitfield.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Link: http://lkml.kernel.org/r/1541516257-16157-2-git-send-email-narmstrong@baylibre.com