Stop using %{name} for things in the spec file
There's no point to this (the packaging isn't generic, confusion between
grub and grub2 in places, it's not fewer characters to type, have to
think about escaping in macros, ...) and it makes searching for things
needlessly difficult.
This finishes the revert of 967c5629ed9fdb4e8572daa78f3bb5ac5e675e77
("Don't harcode grub2 in the spec file") that was begun in
af038a0bdc38f46db45fc5aeaca0a6942fc22440 ("Revert "Don't harcode grub2
in the spec file"").
Signed-off-by: Robbie Harwood <rharwood@redhat.com>