IVGCVSW-IVGCVSW-4772 Fixes for android-nn-driver unit tests on Android R

 * Added missing operand parameter numberOfConsumers to DriverTestHelpers
 * Added nullptr checks to unit tests
 * Disabling QuantizedLstmTest when ARMCOMPUTECL_ENABLED is undefined

Signed-off-by: David Monahan <david.monahan@arm.com>
Change-Id: I46dc413d3bb1805eb0e7c982177b6d60d0b297f5
diff --git a/test/Concurrent.cpp b/test/Concurrent.cpp
index 0694934..aeea17f 100644
--- a/test/Concurrent.cpp
+++ b/test/Concurrent.cpp
@@ -110,6 +110,7 @@
     ALOGI("ConcurrentExecute: waiting for callbacks");
     for (size_t i = 0; i < maxRequests; ++i)
     {
+        ARMNN_ASSERT(cb[i]);
         cb[i]->wait();
     }