Revert "dmaengine: dmatest: timeout value of -1 should specify infinite wait"

This reverts commit ed04b7c5.

While it gives a good description what happens, the approach seems too
confusing. Let's fix it in the following patch.

Cc: Gary Hook <Gary.Hook@amd.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200424161147.16895-3-andriy.shevchenko@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>