9842 man page typos and spelling

*** 251,261 ****
  convert little-endian data to the host's endianness and from the host's
  to little-endian respectively.
  .Pp
  These functions are not standardized and the header they appear in varies
  between the BSDs and GNU/Linux.
! Applications that wish to be portable, shoulda instead use the
  .Xr byteorder 3C
  functions.
  .Pp
  All of these functions in both families simply return their input when
  the host's native byte order is the same as the desired order.
--- 251,261 ----
  convert little-endian data to the host's endianness and from the host's
  to little-endian respectively.
  .Pp
  These functions are not standardized and the header they appear in varies
  between the BSDs and GNU/Linux.
! Applications that wish to be portable, should instead use the
  .Xr byteorder 3C
  functions.
  .Pp
  All of these functions in both families simply return their input when
  the host's native byte order is the same as the desired order.