Modified hipMalloc size for main.cpp in sample (#786)

* Modified hipMalloc size for main.cpp in sample

* Update samples/counter_collection/main.cpp

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Co-authored-by: Jonathan R. Madsen <jrmadsen@users.noreply.github.com>

samples/counter_collection/main.cpp

@@ -77,7 +77,7 @@ launchKernels()
     }
 
     const int NElems = 512 * 512;
-    const int Nbytes = NElems * 2;
+    const int Nbytes = NElems * sizeof(int);
     int *     A_d, *C_d;
     int       A_h[NElems], C_h[NElems];