clk: core: Copy connection id

Some drivers use sprintf to build clk connection id names but the clk
core will save those strings and occasionally print them back. Duplicate
the con_id strings instead of fixing all the users.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>