clk: cdce925: Remove redundant assignment to variable 'rate'

clk: cdce925: Remove redundant assignment to variable 'rate'

The variable 'rate' being assigned a value that is never read, the
assignment is redundant and can be removed.

Cleans up clang scan build warning:
drivers/clk/clk-cdce925.c:104:3: warning: Value stored to 'rate' is
never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20240216140132.2108665-1-colin.i.king@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>