Refactor wimpy feature (#2507)

- Make it a common parameter in harness using either '-w', '--wimpy' or
'CL_WIMPY_MODE' environment variable.
- Remove all test specific wimpy variable.

---------

Co-authored-by: Kévin Petit <kpet@free.fr>

test_conformance/vectors/structs.cpp

@@ -18,6 +18,8 @@
 
 #include "defines.h"
 
+#include "harness/parseParameters.h"
+
 #define DEBUG_MEM_ALLOC 0
 
 /** typedef struct _bufferStruct
@@ -223,7 +225,7 @@ void initContents(bufferStruct *pBufferStruct, clState *pClState,
             break;
         }
         case 4: {
-            if (!g_wimpyMode)
+            if (!gWimpyMode)
             {
                 uint32_t *ui = (uint32_t *)(pBufferStruct->m_pIn);
                 for (i = 0; i < countIn; ++i)