opengl/tests: Don't run Pbuffer tests if no Pbuffer can be created.

dlls/opengl32/tests/opengl.c

@@ -194,9 +194,8 @@ static void test_pbuffers(HDC hdc)
     {
         HDC pbuffer_hdc;
         HPBUFFERARB pbuffer = pwglCreatePbufferARB(hdc, iPixelFormat, 640 /* width */, 480 /* height */, NULL);
-        if(!pbuffer)
-            skip("Pbuffer creation failed!\n");
-
+        if(pbuffer)
+        {
             /* Test the pixelformat returned by GetPixelFormat on a pbuffer as the behavior is not clear */
             pbuffer_hdc = pwglGetPbufferDCARB(pbuffer);
             res = GetPixelFormat(pbuffer_hdc);
@@ -206,6 +205,8 @@ static void test_pbuffers(HDC hdc)
             trace("PixelFormat from wglChoosePixelFormatARB: %d\n", iPixelFormat);
             pwglReleasePbufferDCARB(pbuffer, hdc);
         }
+        else skip("Pbuffer creation failed!\n");
+    }
     else skip("Pbuffer test for offscreen pixelformat skipped as no offscreen-only format with pbuffer capabilities has been found\n");
 }