Keep the same behavior to the return value of FcConfigParseAndLoad

reverting the behavior accidentally changed by 12b750

https://bugs.freedesktop.org/show_bug.cgi?id=102141

src/fcxml.c

@@ -3368,7 +3368,10 @@ FcConfigParseAndLoad (FcConfig	    *config,
 
     f = FcConfigFilename (name);
     if (!f)
+    {
+	ret = FcTrue;
 	goto bail0;
+    }
     if (sysroot)
 	filename = FcStrBuildFilename (sysroot, f, NULL);
     else
@@ -3399,6 +3402,7 @@ FcConfigParseAndLoad (FcConfig	    *config,
     fd = FcOpen ((char *) filename, O_RDONLY);
     if (fd == -1) {
 	FcStrFree (filename);
+	ret = FcTrue;
 	goto bail1;
     }