meson: port python bindings to build natively via meson and meson-python

We get full build parallelism and fewer confusing ancient distutils
paths. The python wheels build fully standalone, including linking
libfdt as a static library.

For convenience, when running pip install a meson option is passed that
prevents building tools or installing headers/pkgconfig files.
meson-python would otherwise include them in the wheel itself, in case
they are needed, but this is essentially a bit useless so don't bother.

The old setuptools-based build is now redundant and goes away.

Signed-off-by: Eli Schwartz <eschwartz@gentoo.org>
Message-ID: <20250430152601.43554-3-eschwartz@gentoo.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

libfdt/meson.build

@@ -31,7 +31,7 @@ libfdt = library(
   version: meson.project_version(),
   link_args: link_args,
   link_depends: 'version.lds',
-  install: true,
+  install: get_option('default_library') != 'static' or not wheel_only,
 )
 
 libfdt_inc = include_directories('.')
@@ -41,20 +41,22 @@ libfdt_dep = declare_dependency(
   link_with: libfdt,
 )
 
-install_headers(
-  files(
-    'fdt.h',
-    'libfdt.h',
-    'libfdt_env.h',
+if not wheel_only
+  install_headers(
+    files(
+      'fdt.h',
+      'libfdt.h',
+      'libfdt_env.h',
+    )
   )
-)
 
-pkgconfig = import('pkgconfig')
+  pkgconfig = import('pkgconfig')
 
-pkgconfig.generate(
-  libraries: libfdt,
-  version: meson.project_version(),
-  filebase: 'libfdt',
-  name: 'libfdt',
-  description: 'Flat Device Tree manipulation',
-)
+  pkgconfig.generate(
+    libraries: libfdt,
+    version: meson.project_version(),
+    filebase: 'libfdt',
+    name: 'libfdt',
+    description: 'Flat Device Tree manipulation',
+  )
+endif