headers/build: Use the system's types.h on Haiku.

Technically a "hack" (but then again most of the config/build stuff is);
as we need to use the system's config/types.h in order to get stdint
definitions and the like.

Previously there was a config_build directory which allowed the existence
of two types.h -- the system one, and the headers/build one, but seeing
as we only need this to provide Haiku-specific core types on other platforms,
using the system's one should be fine.

Our core type definitions have not changed in some time (and it's unclear
when they would change aside from potential new platforms), breakage of the
Haiku-on-Haiku build due to this should not happen often (if ever.)

headers/build: Reunify BeBuild.h and related cleanup.

Now that we do not target BeOS and also do not include the main headers
directory when building "build" binaries, we can drop the separate
config_build directory and thus also the separate BeBuild.h, and just
..-include the regular one.

The build BeBuild.h defined empty _IMPEXP_ROOT and _IMPEXP_BE preprocessor
macros that the regular one does not; so I also re-synchronized
headers which used these as needed.

Renamed headers/build/config to headers/build/config_build, so it doesn't
shadow the host platform's <config/...> headers anymore.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34271 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Don't even try to use the BeOS compatible types on the build platform.
That's just leading to problems.
* Fixed various 64 bit warnings when building libbe_build.so. One of the more
serious issues, that might bite us, is that 64 bit Linux defines dev_t to
unsigned long, while Haiku code assumes that it is signed and 32 bit. We'll
see...


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34227 a95241bf-73f2-0310-859d-f6bbb57e9c96

Updated the build versions of <BeBuild.h> and <SupportDefs.h>. Copied
modified versions of the new config headers.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@34224 a95241bf-73f2-0310-859d-f6bbb57e9c96