As this symbol can either be a fixed value or the function
get_board_ddr_clk, migration is tricky. Introduce a choice of DYNAMIC
or STATIC_DDR_CLK_FREQ. If DYNAMIC, we continue to use the board
defined get_board_ddr_clk function. If STATIC, set CONFIG_DDR_CLK_FREQ
to that value and now include/clock_legacy.h contains the function
prototype or defines get_board_ddr_clk() to that static value. Update
callers to test for DYNAMIC or STATIC.
Signed-off-by: Tom Rini <trini@konsulko.com>
These three clock functions don't use driver model and should be migrated.
In the meantime, create a new file to hold them.
Signed-off-by: Simon Glass <sjg@chromium.org>