EventPipe C library CoreClr ep_rt_object_array_alloc should zero init. (#47111)

EventPipe C library is defensive in its type allocators:

ep_rt_object_alloc
ep_rt_object_array_alloc

meaning that they will zero init memory before returned. On Mono this is
done through use of g_new0 and on CoreClr we use C++11 zero init feature
when allocating struct (only type allocated through these functions).

On CoreClr this was only applied for ep_rt_object_alloc but not for
ep_rt_object_array_alloc meaning that ep_rt_object_array_alloc would
return arrays of allocated objects but not zero initialized.

PR makes sure we call new (nothrow) utilizing C++11's zero initialization
capabilities of non-class types without constructors.

Author: lateralusX

src/coreclr/vm/eventing/eventpipe/ep-rt-coreclr.h

@@ -1891,7 +1891,7 @@ ep_rt_execute_rundown (void)
 
 // STATIC_CONTRACT_NOTHROW
 #undef ep_rt_object_array_alloc
-#define ep_rt_object_array_alloc(obj_type,size) (new (nothrow) obj_type [size])
+#define ep_rt_object_array_alloc(obj_type,size) (new (nothrow) obj_type [size]())
 
 // STATIC_CONTRACT_NOTHROW
 #undef ep_rt_object_array_free