Increase the number of work items used by the allocations test (#1852)

* Increase the number of work items used by the allocations test

The test uses a fixed number of work items to process very large
buffers and images. As devices support more and more memory, this
leads to an ever-increasing amount of work done in each work item.
This results in some implementations and devices hitting timeout
issues.

Furthermore, a greater number of work items can provide performance
benefits on some devices.

Long term, this test should be redesigned to scale the number
of threads dynamically as a function of the max allocation size.

Signed-off-by: Kevin Petit <kevin.petit@arm.com>

* formatting and add parentheses

---------

Signed-off-by: Kevin Petit <kevin.petit@arm.com>

test_conformance/allocations/allocation_execute.cpp

@@ -140,7 +140,7 @@ int check_image(cl_command_queue queue, cl_mem mem) {
 }
 
 
-#define NUM_OF_WORK_ITEMS 8192*2
+#define NUM_OF_WORK_ITEMS (8192 * 32)
 
 int execute_kernel(cl_context context, cl_command_queue *queue, cl_device_id device_id, int test, cl_mem mems[], int number_of_mems_used, int verify_checksum) {