clk: sprd: mark the local clock symbols static

clk: sprd: mark the local clock symbols static

There's a few pll gate clocks which were not marked with static, and
those clock are used only in the current file, so add static key word
for them.

Fixes: b4ca7dbbbc1d ("clk: sprd: add clocks support for SC9863A")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lkml.kernel.org/r/20200519030036.1785-1-zhang.lyra@gmail.com
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>