tree-wide: add dlopen ELF notes to all dlopen() deps of ours

Use 'recommended' priority for the default compression library, to
indicate that it should be prioritized over the other ones, as it
will be used to compress journals/core files.
Also use 'recommended' for kmod, as systems will likely fail to boot
if it's missing from the initrd.
Use 'suggested' for everything else.

There is one dlopen'ed TPM library that has the name generated
at runtime (depending on the driver), so that cannot be added, as it
needs to be known at build time.
Also when we support multiple ABI versions list them all, as for the
same reason we cannot know which one will be used at build time.

$ dlopen-notes.py build/libsystemd.so.0.39.0 build/src/shared/libsystemd-shared-256.so
libarchive.so.13 suggested
libbpf.so.0 suggested
libbpf.so.1 suggested
libcryptsetup.so.12 suggested
libdw.so.1 suggested
libelf.so.1 suggested
libfido2.so.1 suggested
libgcrypt.so.20 suggested
libidn2.so.0 suggested
libip4tc.so.2 suggested
libkmod.so.2 recommended
liblz4.so.1 suggested
liblzma.so.5 suggested
libp11-kit.so.0 suggested
libpcre2-8.so.0 suggested
libpwquality.so.1 suggested
libqrencode.so.3 suggested
libqrencode.so.4 suggested
libtss2-esys.so.0 suggested
libtss2-mu.so.0 suggested
libtss2-rc.so.0 suggested
libzstd.so.1 recommended

Co-authored-by: Luca Boccassi <bluca@debian.org>

src/basic/compress.c

@@ -129,6 +129,11 @@ bool compression_supported(Compression c) {
 
 #if HAVE_XZ
 int dlopen_lzma(void) {
+        ELF_NOTE_DLOPEN("lzma",
+                        "Support lzma compression in journal and coredump files",
+                        COMPRESSION_PRIORITY_XZ,
+                        "liblzma.so.5");
+
         return dlopen_many_sym_or_warn(
                         &lzma_dl,
                         "liblzma.so.5", LOG_DEBUG,
@@ -186,6 +191,11 @@ int compress_blob_xz(const void *src, uint64_t src_size,
 
 #if HAVE_LZ4
 int dlopen_lz4(void) {
+        ELF_NOTE_DLOPEN("lz4",
+                        "Support lz4 compression in journal and coredump files",
+                        COMPRESSION_PRIORITY_LZ4,
+                        "liblz4.so.1");
+
         return dlopen_many_sym_or_warn(
                         &lz4_dl,
                         "liblz4.so.1", LOG_DEBUG,
@@ -242,6 +252,11 @@ int compress_blob_lz4(const void *src, uint64_t src_size,
 
 #if HAVE_ZSTD
 int dlopen_zstd(void) {
+        ELF_NOTE_DLOPEN("zstd",
+                        "Support zstd compression in journal and coredump files",
+                        COMPRESSION_PRIORITY_ZSTD,
+                        "libzstd.so.1");
+
         return dlopen_many_sym_or_warn(
                         &zstd_dl,
                         "libzstd.so.1", LOG_DEBUG,

src/basic/gcrypt-util.c

@@ -41,6 +41,11 @@ DLSYM_FUNCTION(gcry_randomize);
 DLSYM_FUNCTION(gcry_strerror);
 
 static int dlopen_gcrypt(void) {
+        ELF_NOTE_DLOPEN("gcrypt",
+                        "Support for journald forward-sealing",
+                        ELF_NOTE_DLOPEN_PRIORITY_SUGGESTED,
+                        "libgcrypt.so.20");
+
         return dlopen_many_sym_or_warn(
                         &gcrypt_dl,
                         "libgcrypt.so.20", LOG_DEBUG,