NFC: digital: Remove two unused macroes

DIGITAL_NFC_DEP_REQ_RES_TAILROOM is never used after it was introduced.
DIGITAL_NFC_DEP_REQ_RES_HEADROOM is no more used after below
commit e8e7f421

 ("NFC: digital: Remove useless call to skb_reserve()")
Remove them.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>