setuptools_build_meta.bbclass: add helper class

This class uses the PEP 517 compliant setuptools.buil_meta to build
wheels.

[YOCTO #14638]

(From OE-Core rev: b8f25c75f152683de4fa6c176118583d3dea894d)

Signed-off-by: Tim Orling <tim.orling@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/setuptools_build_meta.bbclass

@@ -0,0 +1,18 @@
+inherit pip_install_wheel setuptools3-base
+
+DEPENDS += "python3 python3-setuptools-native python3-wheel-native"
+
+setuptools_build_meta_do_configure () {
+    mkdir -p ${S}/dist
+    cat > ${S}/build-it.py << EOF
+from setuptools import build_meta
+wheel = build_meta.build_wheel('./dist')
+print(wheel)
+EOF
+}
+
+setuptools_build_meta_do_compile () {
+    nativepython3 ${S}/build-it.py
+}
+
+EXPORT_FUNCTIONS do_configure do_compile