dmatest: move src_off, dst_off, len inside loop
dmatest: move src_off, dst_off, len inside loop

The scope of those varsiables is in while-loop. This patch moves them there and
removes duplicate code.

Signed-off-by: Andy Shevchenko <74f0c009df510614346aa771cd21959b78cdb413@linux.intel.com>
Signed-off-by: Vinod Koul <5cf69c63beb17bf38d63aa0e923ee8256af0e205@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs