Changing default X11_TYPE from native to modular for some platforms (Was: What platforms work with X11_TYPE=native)

[David Brownlee <abs%netbsd.org@localhost>]

Based on the responses I'm going to switch the default X11_TYPE to be
modular, and override in platform/*.mk files as required. The new
values will be:

Changed - from native to modular
- FreeBSD
- FreeMiNT
- Linux

Changed - older versions switched from native to modular
- NetBSD - native for NetBSD-4 and later

Native (unchanged)  - should probably be switched to modular
- AIX
- BSDOS
- IRIX
- Interix
- MirBSD
- UnixWare

Native (unchanged)
- Darwin - for Leopard (10.5) and later
- OpenBSD.mk
- SunOS.mk

Modular (unchanged)
- DragonFly
- HPUX
- Haiku
- OSF1

I'd like to encourage anyone using X11 apps on any platforms other
than NetBSD, Darwin, DragonFly, FreeBSD, Linux, FreeMiNT, HPUX, Haiku
or OSF1 to speak up, whether they are happy with native or having to
set modular.