meson: do not link libshared dynamically against libudev (#5850)

Linking dynamically against libudev will fail once
https://github.com/mesonbuild/meson/pull/1545 is merged and apparently
already triggers a link failure on s390x.

Make libshared provide the udev symbols by including libudev_sources
into libshared. This will cause those files to be compiled twice, but it
actually reduces the installed size and is closer to what the autotools
build system is doing.

Closes #5828

src/shared/meson.build

@@ -127,10 +127,10 @@ libshared = shared_library(
         basic_sources,
         journal_internal_sources,
         libsystemd_internal_sources,
+        libudev_sources,
         include_directories : includes,
         link_args : ['-shared'],
         c_args : ['-fvisibility=default'],
-        link_with : [libudev],
         dependencies : [threads,
                         librt,
                         libcap,