iavf: remove redundant ret variable

[ Upstream commit c3fec56e ]

Return value directly instead of taking this in another redundant
variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Signed-off-by: CGEL ZTE <cgel.zte@gmail.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Stable-dep-of: 227d8d2f ("iavf: Fix error handling in iavf_init_module()")
Signed-off-by: Sasha Levin <sashal@kernel.org>