Reduce the max number of concurrent pipeline cache objects

Previous maximum of 16k was excessive as these objects are expected to
have a significant size. Estimating their size based on allocation
callbacks may be not representative of the actual memory usage.

Affected tests:

dEQP-VK.api.object_management.max_concurrent.pipeline_cache

Components: Vulkan
VK-GL-CTS issue: 539

Change-Id: I17a868b993a55296417eee80dfa15c5559e4c20e
diff --git a/external/vulkancts/modules/vulkan/api/vktApiObjectManagementTests.cpp b/external/vulkancts/modules/vulkan/api/vktApiObjectManagementTests.cpp
index b65821a..c07b8a1 100644
--- a/external/vulkancts/modules/vulkan/api/vktApiObjectManagementTests.cpp
+++ b/external/vulkancts/modules/vulkan/api/vktApiObjectManagementTests.cpp
@@ -955,7 +955,7 @@
 
 	static deUint32 getMaxConcurrent (Context&)
 	{
-		return DEFAULT_MAX_CONCURRENT_OBJECTS;
+		return 128;
 	}
 
 	struct Parameters