* grub-core/tests/div_test.c: New test.

grub-core/Makefile.core.def

@@ -1855,6 +1855,11 @@ module = {
   common = tests/setjmp_test.c;
 };
 
+module = {
+  name = div_test;
+  common = tests/div_test.c;
+};
+
 module = {
   name = videotest_checksum;
   common = tests/videotest_checksum.c;