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/half/main.cpp

@@ -178,9 +178,6 @@ static int ParseArgs( int argc, const char **argv )
 
                     case 'r': gHostReset = true; break;
 
-                    case 'w':  // Wimpy mode
-                        gWimpyMode = true;
-                        break;
                     case '[':
                         parseWimpyReductionFactor( arg, gWimpyReductionFactor);
                         break;
@@ -199,12 +196,6 @@ static int ParseArgs( int argc, const char **argv )
         }
     }
 
-    if (getenv("CL_WIMPY_MODE")) {
-      vlog( "\n" );
-      vlog( "*** Detected CL_WIMPY_MODE env                          ***\n" );
-      gWimpyMode = 1;
-    }
-
     PrintArch();
     if( gWimpyMode )
     {
@@ -234,7 +225,6 @@ static void PrintUsage( void )
          "supported)\n");
     vlog("\t\t-t\tToggle reporting performance data.\n");
     vlog("\t\t-r\tReset buffers on host instead of on device.\n");
-    vlog("\t\t-w\tRun in wimpy mode\n");
     vlog("\t\t-[2^n]\tSet wimpy reduction factor, recommended range of n is "
          "1-12, default factor(%u)\n",
          gWimpyReductionFactor);