ti: am33xx: fix do_enable_clocks() to accept NULL parameters

Up till this commit passing NULL as input parameter was allowed, but not
handled properly. When a NULL parameter was passed to the function a data
abort was raised.

Signed-off-by: Dario Binacchi <dariobin@libero.it>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed