Some small, random additions to the .gitignore.

Ignores some auxiliary files generated/used by the following tools: -

- clangd
- GNU Global
- Emacs

.gitignore

@@ -61,6 +61,8 @@ named.memstats
 named.run
 timestamp
 /compile_commands.json
+# Gets generated by Build Ear (bear)
+/compile_commands.commands.json
 /cppcheck_html/
 /cppcheck.results
 /tsan
@@ -87,3 +89,13 @@ doc/man/pkcs11-destroy.8in
 doc/man/pkcs11-keygen.8in
 doc/man/pkcs11-list.8in
 doc/man/pkcs11-tokens.8in
+# clangd index directory
+/\.cache/
+# GNU Global index files
+/GPATH
+/GRTAGS
+/GTAGS
+# Emacs specific files
+\.dir-locals-2.el
+/emacs.desktop
+/emacs.desktop-lock