clk: samsung: Remove redundant check in samsung_cmu_register_one

Consistent with other instances of samsung_clk_init, the check
if ctx is NULL is redundant. The function currently does not
return NULL.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Link: https://lkml.kernel.org/r/20200121233349.28627-1-pakki001@umn.edu
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>