buildroot

efibootmgr: bump to version 14

Upstream has changed version numbering scheme since version 13, which
came after version 0.12.

There is now a make install target, so we can drop the manual file
installing. The make install target also installs the new efibootdump
tool.

Signed-off-by: Erico Nunes <nunes.erico@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>