i40e: fix vf may be used uninitialized in this function warning

To fix the regression introduced by commit 52424f97, which causes
servers hang in very hard to reproduce conditions with resets races.
Using two sources for the information is the root cause.
In this function before the fix bumping v didn't mean bumping vf
pointer. But the code used this variables interchangeably, so stale vf
could point to different/not intended vf.

Remove redundant "v" variable and iterate via single VF pointer across
whole function instead to guarantee VF pointer validity.

Fixes: 52424f97

 ("i40e: Fix VF hang when reset is triggered on another VF")
Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>