meson: create a static version of libshared and link libcore and some tests to it

This is what autoconf-based build does, and it makes test-bus-error and
test-engine able to access the bus error mapping table. OTOH, this is a heavy
price to pay: it would be excellent to link libcore.a to libsystemd-shared-NNN.so.
Otherwise we duplicate the same code in 'systemd' and 'libsystemd-shared-NNN.so'.

-rwxrwxr-x. 1 4075544 Apr  6 20:30 systemd* <-- libcore linked against libsystemd-shared.so
-rwxrwxr-x. 1 5596504 Apr  9 14:07 systemd* <-- libcore linked against libsystemd-shared.a

v2:
- update for 6b5cf3ea62

src/test/meson.build

@@ -23,40 +23,60 @@ tests += [
    []],
 
   [['src/test/test-engine.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-job-type.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-ns.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount],
+    libmount,
+    libblkid],
    '', 'unsafe'],
 
   [['src/test/test-loopback.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-hostname.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount],
+    libmount,
+    libblkid],
    '', 'unsafe'],
 
   [['src/test/test-dns-domain.c'],
@@ -70,18 +90,26 @@ tests += [
    'ENABLE_EFI'],
 
   [['src/test/test-unit-name.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-unit-file.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-utf8.c'],
    [libshared],
@@ -100,7 +128,7 @@ tests += [
    []],
 
   [['src/test/test-copy.c'],
-   [libshared],
+   [libshared_static],
    []],
 
   [['src/test/test-sigbus.c'],
@@ -237,8 +265,10 @@ tests += [
    []],
 
   [['src/test/test-namespace.c'],
-   [libcore],
-   []],
+   [libcore,
+    libudev,
+    libsystemd],
+   [libblkid]],
 
   [['src/test/test-verbs.c'],
    [libshared],
@@ -407,11 +437,15 @@ tests += [
 
 
   [['src/test/test-cgroup-mask.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-cgroup-util.c'],
    [libshared],
@@ -434,18 +468,26 @@ tests += [
    []],
 
   [['src/test/test-path.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-execute.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-siphash24.c'],
    [libshared],
@@ -456,7 +498,8 @@ tests += [
    []],
 
   [['src/test/test-install.c'],
-   [libcore],
+   [libcore,
+    libsystemd],
    [],
    '', 'manual'],
 
@@ -465,11 +508,15 @@ tests += [
    []],
 
   [['src/test/test-sched-prio.c'],
-   [libcore],
-   [librt,
+   [libcore,
+    libudev,
+    libsystemd],
+   [threads,
+    librt,
     libseccomp,
     libselinux,
-    libmount]],
+    libmount,
+    libblkid]],
 
   [['src/test/test-conf-files.c'],
    [libshared],
@@ -611,6 +658,15 @@ tests += [
 
 ############################################################
 
+tests += [
+  [['src/libsystemd/sd-bus/test-bus-error.c'],
+   [libshared_static,
+    libsystemd],
+   []],
+  ]
+
+############################################################
+
 tests += [
   [['src/libsystemd-network/test-dhcp-option.c',
     'src/libsystemd-network/dhcp-protocol.h',