ste_dma40: Move an assignment in d40_lcla_allocate()

Move one assignment for the local variable "ret" so that its setting
will only be performed after corresponding data processing succeeded
by this function.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>