* packages/ada-mode: Miscellaneous tweaks to fix warnings

* packages/ada-mode: Miscellaneous tweaks to fix warnings

* packages/ada-mode/ada-mode.el (ada-in-numeric-literal-p): Refine call to
looking-back.
(<toplevel>): Fix broken use of cl-case.

* packages/ada-mode/ada-skel.el: Use #' to quote function names.

* packages/ada-mode/ada-wisi.el (ada-wisi-which-function-1): Remove unused var
`region' and avoid unneeded setq.

* packages/ada-mode/gnat-inspect.el (gnat-inspect-compilation):
* packages/ada-mode/gpr-query.el (gpr-query-compilation): Silence warning.