staging/rdma/hfi1: diag.c add missing braces

Else statements should continue using braces even if there is only 1 line in
the block.  Found by checkpatch --strict

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>