test/memory: fix autotest parsing

test/memory: fix autotest parsing

This patch fixes three problems in memory autotest:
 - the regex for IOVA
 - missing validation of second and following output lines
 - propagation of error to consecutive tests
 - conversion base for mem size (hex indtead of dec)
First fix is for changes introduced with IOVA, the regex was not
updated which lead to unit test failure.  Patch now also uses loop for
line outputs processing to verify more than just one line. By this we
also satisfy the pexpect() and scan the "Test OK"/"Test Failed" so in
case of error all output lines are consumed and does not break the
consecutive test (error does not propagate).

Fixes: 7ba49d39f14c ("mem: rename segment address from physical to IOVA")
Fixes: b4ce15aa2bc7 ("app/test: fix memory autotest")

Signed-off-by: Radoslaw Biernacki <radoslaw.biernacki@linaro.org>