ice: move ice_is_malicious_vf() to ice_virtchnl.c

ice: move ice_is_malicious_vf() to ice_virtchnl.c

The ice_is_malicious_vf() function is currently implemented in ice_sriov.c
This function is not Single Root specific, and a future change is going to
refactor the ice_vc_process_vf_msg() function to call this instead of
calling it before ice_vc_process_vf_msg() in the main loop of
__ice_clean_ctrlq.

To make that change easier to review, first move this function into
ice_virtchnl.c but leave the call in __ice_clean_ctrlq() alone.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: Marek Szlosek <marek.szlosek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>