IB/hfi1: Fix a typo

s/struture/structure/

And add the missing colon for kdoc

Link: https://lore.kernel.org/r/20210322062923.3306167-1-unixbhaskar@gmail.com


Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>