net/mlx5: Fix some spelling mistakes

Fixed few places where endianness was misspelled and
one spot whwere output was:

CHECK: 'endianess' may be misspelled - perhaps 'endianness'?
CHECK: 'ouput' may be misspelled - perhaps 'output'?

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>