meson: add alias targets to group nss and pam modules

Add aliases grouping these modules, so that they can be built
without knowing the SONAME version in advance. Match the install
tag names.

meson.build

@@ -2527,6 +2527,8 @@ alias_target('fuzzers', fuzzer_exes)
 
 test_dlopen = executables_by_name.get('test-dlopen')
 
+nss_targets = []
+pam_targets = []
 foreach dict : modules
         name = dict.get('name')
         is_nss = name.startswith('nss_')
@@ -2575,6 +2577,11 @@ foreach dict : modules
                 # Unfortunately shared_library insists on creating the symlink…
                 meson.add_install_script(sh, '-c', 'rm $DESTDIR@0@/lib@1@.so'.format(libdir, name),
                                          install_tag : 'nss')
+                nss_targets += lib
+        endif
+
+        if is_pam
+                pam_targets += lib
         endif
 
         if want_tests != 'false' and (is_nss or is_pam)
@@ -2587,6 +2594,14 @@ foreach dict : modules
         endif
 endforeach
 
+# We need the actual targets to build aliases
+if nss_targets.length() > 0
+        alias_target('nss', nss_targets)
+endif
+if pam_targets.length() > 0
+        alias_target('pam', pam_targets)
+endif
+
 #####################################################################
 
 ukify = custom_target(