test_load: Add some y4m checks

test/images/icon-64.y4m

@@ -0,0 +1 @@
+icon-64.yuv444p.y4m

test/test_load.cpp

@@ -55,6 +55,10 @@ static const char  *const pfxs[] = {
 #endif
    "xbm",
    "xpm",
+#ifdef BUILD_Y4M_LOADER
+   "y4m",
+#endif
+
 #ifdef BUILD_BZ2_LOADER
    "ff.bz2",                    // bz2
 #endif
@@ -217,6 +221,8 @@ test_load(void)
         err = close(fd);
         EXPECT_NE(err, 0);
 
+        if (!strcmp(pfxs[i], "y4m"))    // y4m cannot do mem
+           continue;
         if (!strcmp(pfxs[i], "jpg.mp3"))        // id3 cannot do mem
            continue;
 

test/test_load_2.cpp

@@ -84,6 +84,11 @@ static tii_t        tii[] = {
 #endif
    { "icon-64.xbm",		3936773892 },
    { "icon-64.xpm",		4016720483 },
+#ifdef BUILD_Y4M_LOADER
+   { "icon-64.yuv420p.y4m",	3810593176 },
+   { "icon-64.yuv422p.y4m",	2809447983 },
+   { "icon-64.yuv444p.y4m",	2400380696 },
+#endif
 
    { "icon-128.ico",		 218415319 },
    { "icon-128-d1.ico",		3776822558 },