IB/usnic: Append documentation to usnic_transport.h and cleanup

Add comment describing usnic_transport_rsrv port and remove
extraneous space from usnic_transport.c.
Signed-off-by: NUpinder Malhi <umalhi@cisco.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>

drivers/infiniband/hw/usnic/usnic_transport.c

@@ -184,7 +184,6 @@ int usnic_transport_sock_get_addr(struct socket *sock, int *proto,
 	return 0;
 }
 
-
 int usnic_transport_init(void)
 {
 	roce_bitmap = kzalloc(ROCE_BITMAP_SZ, GFP_KERNEL);

drivers/infiniband/hw/usnic/usnic_transport.h

@@ -28,6 +28,10 @@ const char *usnic_transport_to_str(enum usnic_transport_type trans_type);
  */
 int usnic_transport_sock_to_str(char *buf, int buf_sz,
 					struct socket *sock);
+/*
+ * Reserve a port. If "port_num" is set, then the function will try
+ * to reserve that particular port.
+ */
 u16 usnic_transport_rsrv_port(enum usnic_transport_type type, u16 port_num);
 void usnic_transport_unrsrv_port(enum usnic_transport_type type, u16 port_num);
 /*