buildtools-tarball: Add texinfo (for makeinfo)

Initially I was reluctant to do this however makeinfo is a dependency
of the buildsystem and only adds around 400kb to the buildtools-tarball
so it likely makes sense to add it. This allows people to use
the project on older environments.

Need to enable nativesdk-texinfo but this seems straightforward.

[YOCTO #8990]

(From OE-Core rev: 5e290201e13a685818ff03ad9cd6679977e560d1)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/meta/buildtools-tarball.bb

@@ -23,6 +23,7 @@ TOOLCHAIN_HOST_TASK ?= "\
     nativesdk-make \
     nativesdk-wget \
     nativesdk-ca-certificates \
+    nativesdk-texinfo \
     "
 
 SDK_PACKAGE_ARCHS =+ "buildtools-dummy-${SDKPKGSUFFIX}"

meta/recipes-extended/texinfo/texinfo_6.0.bb

@@ -79,4 +79,4 @@ FILES_${PN}-doc = "${infodir}/texinfo* \
                    ${datadir}/${tex_texinfo} \
                    ${mandir}/man1 ${mandir}/man5"
 
-BBCLASSEXTEND = "native"
+BBCLASSEXTEND = "native nativesdk"