qed: Fix mask parameter in qed_vf_prep_tunn_req_tlv

Clang complains when one enumerated type is implicitly converted to
another.

drivers/net/ethernet/qlogic/qed/qed_vf.c:686:6: warning: implicit
conversion from enumeration type 'enum qed_tunn_mode' to different
enumeration type 'enum qed_tunn_clss' [-Wenum-conversion]
                                 QED_MODE_L2GENEVE_TUNN,
                                 ^~~~~~~~~~~~~~~~~~~~~~

Update mask's parameter to expect qed_tunn_mode, which is what was
intended.

Link: https://github.com/ClangBuiltLinux/linux/issues/125


Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>