opengl32/tests: Use BOOL type where appropriate.

dlls/opengl32/tests/opengl.c

@@ -343,7 +343,7 @@ static void test_setpixelformat(HDC winhdc)
 static void test_sharelists(HDC winhdc)
 {
     HGLRC hglrc1, hglrc2, hglrc3;
-    int res;
+    BOOL res;
 
     hglrc1 = wglCreateContext(winhdc);
     res = wglShareLists(0, 0);
@@ -451,7 +451,7 @@ static void test_colorbits(HDC hdc)
     int iAttribRet[sizeof(iAttribList)/sizeof(iAttribList[0])];
     const int iAttribs[] = { WGL_ALPHA_BITS_ARB, 1, 0 };
     unsigned int nFormats;
-    int res;
+    BOOL res;
     int iPixelFormat = 0;
 
     if (!pwglChoosePixelFormatARB)
@@ -486,7 +486,7 @@ static void test_gdi_dbuf(HDC hdc)
     int iAttribRet[sizeof(iAttribList)/sizeof(iAttribList[0])];
     unsigned int nFormats;
     int iPixelFormat;
-    int res;
+    BOOL res;
 
     if (!pwglGetPixelFormatAttribivARB)
     {
@@ -730,7 +730,8 @@ static void test_deletecontext(HWND hwnd, HDC hdc)
     struct wgl_thread_param thread_params;
     HGLRC hglrc = wglCreateContext(hdc);
     HANDLE thread_handle;
-    DWORD res, tid;
+    BOOL res;
+    DWORD tid;
 
     SetLastError(0xdeadbeef);
     res = wglDeleteContext(NULL);