Disable msan errors on null allocation in all.sh

Such error was raised in platform tests,
and it's a valid test case.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 46d249d..604b457 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -191,6 +191,7 @@
 
     # Platform tests have an allocation that returns null
     export ASAN_OPTIONS="allocator_may_return_null=1"
+    export MSAN_OPTIONS="allocator_may_return_null=1"
 
     # Gather the list of available components. These are the functions
     # defined in this script whose name starts with "component_".