* util/update-grub_lib.in: Copy to ...
* util/grub-mkconfig_lib.in: ... this. Update all users.
* util/update-grub_lib.in: Make it a stub to `grub-mkconfigig_lib.in'.
* util/update-grub.in: Rename to ...
* util/grub-mkconfig.in: ... this. Update all users. Remove `-y'
option. Add `--output' option to allow users to specify the generated
configuration file. Default to stdout.
(update_grub_dir): Rename to ...
(grub_mkconfig_dir): ... this.
(grub_cfg): Default to an empty string.
* conf/common.rmk (update-grub): Rename to ...
(grub-mkconfig): ... this.
(update-grub_lib): Copy to ...
(grub-mkconfig_lib): ... this.
(update-grub_SCRIPTS): Copy to ...
(grub-mkconfig_SCRIPTS): ... this. Update all users.
(update-grub_DATA): Rename to ...
(grub-mkconfig_DATA): ... this.
