ixgbevf: Remove unused function declarations

ixgbe_napi_add_all()/ixgbe_napi_del_all() are declared but never implemented in
commit 92915f71

 ("ixgbevf: Driver main and ethool interface module and main header")

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230803141904.15316-1-yuehaibing@huawei.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>