staging: rdma: hfi1: Compress return logic

Simplified function return by merging assignment and return into
one line.

Found with Coccinelle.

@@
expression e;
local idexpression ret;
@@
- ret =
+ return
e;
- return ret;

@@ type T; identifier x; @@
- T x;
... when != x

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>