tests/qtest/npcm7xx_rng-test: count runs properly
The number of runs is equal to the number of 0-1 and 1-0 transitions,
plus one. Currently, it's counting the number of times these transitions
do _not_ happen, plus one.
Source:
https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-22r1a.pdf
section 2.3.4 point (3).
Signed-off-by: Havard Skinnemoen <hskinnemoen@google.com>
Message-id:
20201103011457.
2959989-2-hskinnemoen@google.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>