ste_dma40: Delete unnecessary variable initialisations in d40_hw_detect_init()

Five local variables will be set to an appropriate value a bit later.
Thus omit the explicit initialisation which became unnecessary with
a previous update step.

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>