usb: fotg210-udc: Remove a useless assignment

There is no need to use an intermediate array for these memory allocations,
so, axe it.

While at it, turn a '== NULL' into a shorter '!' when testing memory
allocation failure.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/deab9696fc4000499470e7ccbca7c36fca17bd4e.1668458274.git.christophe.jaillet@wanadoo.fr


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>