If 'perm_invent' is preset in player's options, have X11 show the
persistent inventory window from the start instead of waiting for
an 'i' command. moveloop() prolog needed a tweak do deal with it
cleanly.
Require WC_PERM_INVENT in order to honor the perm_invent option.
X11 and curses already set that, tty and curses don't support it,
so only Windows GUI needed to be updated for it.
8fff588ab3