xcb-proto: don't compile for Python 2

Remove the do_install_append to create the Python 2 pyc files, as nothing in the
build is using Python 2 anymore (libxcb is the only user, and that uses Python
3).

Also use variables instead of a patch to control what Python binary and path the
modules are installed to.

(From OE-Core rev: c27c60fe012bf42ea3b22fc1b4496450dc68b50b)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-graphics/xorg-proto/xcb-proto/no-python-native.patch

@@ -1,27 +0,0 @@
-Upstream uses AM_PATH_PYTHON to find a python binary and ask it where to install
-libraries.  This means we either need to depend on python-native (large build
-dependency, early in the build) or use the host python (pythondir reflects the
-host and not the target, breaks builds).
-
-The third option is to just hardcode the path where the module goes, as most
-callers of the code use pkg-config to find where it was installed anyway.
-
-Upstream-Status: Inappropriate
-Signed-off-by: Ross Burton <ross.burton@intel.com>
-
-diff --git a/configure.ac b/configure.ac
-index d140bfe..c7b68da 100644
---- a/configure.ac
-+++ b/configure.ac
-@@ -14,7 +14,10 @@ if test "$XMLLINT" = "no"; then
-    AC_MSG_WARN([xmllint not found; unable to validate against schema.])
- fi
-
--AM_PATH_PYTHON([2.5])
-+pythondir="${libdir}/xcb-proto"
-+AC_SUBST(pythondir)
-+PYTHON="python3"
-+AC_SUBST(PYTHON)
-
- xcbincludedir='${datadir}/xcb'
- AC_SUBST(xcbincludedir)

meta/recipes-graphics/xorg-proto/xcb-proto_1.12.bb

@@ -11,8 +11,7 @@ LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://COPYING;md5=d763b081cb10c223435b01e00dc0aba7 \
                     file://src/dri2.xml;beginline=2;endline=28;md5=f8763b13ff432e8597e0d610cf598e65"
 
-SRC_URI = "http://xcb.freedesktop.org/dist/xcb-proto-${PV}.tar.bz2 \
-           file://no-python-native.patch \
+SRC_URI = "http://xcb.freedesktop.org/dist/${BP}.tar.bz2 \
            file://0001-Make-whitespace-use-consistent.patch \
            file://0002-print-is-a-function-and-needs-parentheses.patch \
            "
@@ -21,6 +20,10 @@ SRC_URI[sha256sum] = "5922aba4c664ab7899a29d92ea91a87aa4c1fc7eb5ee550325c3216c48
 
 inherit autotools pkgconfig
 
+# Force the use of Python 3 and a specific library path so we don't need to
+# depend on python3-native
+CACHED_CONFIGUREVARS += "PYTHON=python3 am_cv_python_pythondir=${libdir}/xcb-proto"
+
 PACKAGES += "python-xcbgen"
 
 FILES_${PN} = ""
@@ -31,10 +34,3 @@ RDEPENDS_${PN}-dev = ""
 RRECOMMENDS_${PN}-dbg = "${PN}-dev (= ${EXTENDPKGV})"
 
 BBCLASSEXTEND = "native nativesdk"
-
-do_install_append() {
-    # Makefile's do_install creates .pyc files for python3, now also create
-    # them for python2 so that they will be recorded by manifest, and can be
-    # cleaned correctly.
-    (cd ${D}; python -m py_compile ./${libdir}/xcb-proto/xcbgen/*.py)
-}