MPS Reader Tests: Add random test

This commit adds a test exercising the reader in a random way
and comparing the outcomes against what we expect based on the
abstract model of the reader from the producer's and consumer's
perspective.

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/tests/suites/test_suite_mps.data b/tests/suites/test_suite_mps.data
index d9f7c42..a751cfa 100644
--- a/tests/suites/test_suite_mps.data
+++ b/tests/suites/test_suite_mps.data
@@ -77,4 +77,16 @@
 mbedtls_mps_reader_multiple_pausing:2
 
 MPS Reader: Pausing several times, #3
-mbedtls_mps_reader_multiple_pausing:3
\ No newline at end of file
+mbedtls_mps_reader_multiple_pausing:3
+
+MPS Reader: Random usage, 20 rds, feed 100, get 200, acc 50
+mbedtls_mps_reader_random_usage:20:100:200:50
+
+MPS Reader: Random usage, 1000 rds, feed 10, get 100, acc 80
+mbedtls_mps_reader_random_usage:1000:10:100:80
+
+MPS Reader: Random usage, 10000 rds, feed 1, get 100, acc 80
+mbedtls_mps_reader_random_usage:10000:1:100:80
+
+MPS Reader: Random usage, 100 rds, feed 100, get 1000, acc 500
+mbedtls_mps_reader_random_usage:100:100:1000:500