community/libxml++-2.6: upgrade to 2.42.0

Switch to meson build system too and drop docs package as it only
contains html from doxygen
8 jobs for !21107 with libxml++-2.6-community in 1 minute and 34 seconds (queued for 1 second)
latest detached
Status Job ID Name Coverage
  Lint
passed #390015
docker-alpine x86_64
lint

00:00:19

 
  Build
passed #390020
docker-alpine ci-build aarch64
build-aarch64

00:00:57

passed #390022
docker-alpine ci-build armhf
build-armhf

00:00:54

passed #390021
docker-alpine ci-build armv7
build-armv7

00:00:53

passed #390019
docker-alpine ci-build ppc64le
build-ppc64le

00:01:05

passed #390018
docker-alpine ci-build s390x
build-s390x

00:01:13

passed #390017
docker-alpine ci-build x86
build-x86

00:00:27

passed #390016
docker-alpine ci-build x86_64
build-x86_64

00:00:25