code review from Josh and Robert

*** 33,43 ****
  .It Fa vmp
  The vmem arena to which the span should be added.
  .It Fa vaddr
  The base address of the span to add.
  .It Fa size
! The size of the span to add
  .It Fa vmflag
  Flags affecting the allocation of the span to add.
  .El
  .Sh DESCRIPTION
  The
--- 33,43 ----
  .It Fa vmp
  The vmem arena to which the span should be added.
  .It Fa vaddr
  The base address of the span to add.
  .It Fa size
! The size of the span to add.
  .It Fa vmflag
  Flags affecting the allocation of the span to add.
  .El
  .Sh DESCRIPTION
  The
*** 51,61 ****
  may allocate.
  .Pp
  .Dv VM_SLEEP
  or
  .Dv VM_NOSLEEP
! must be specified, and indicate whether the addition may block.
  .Sh CONTEXT
  This function can be called from either user or kernel context.
  If the
  .Dv VM_NOSLEEP
  flag is specified, it may also be called from interrupt context.
--- 51,63 ----
  may allocate.
  .Pp
  .Dv VM_SLEEP
  or
  .Dv VM_NOSLEEP
! must be specified in
! .Fa vmflag ,
! and indicate whether the addition may block.
  .Sh CONTEXT
  This function can be called from either user or kernel context.
  If the
  .Dv VM_NOSLEEP
  flag is specified, it may also be called from interrupt context.