efibootmgr: 0.6.0 -> 0.12

Upgrade efibootmgr from 0.6.0 to 0.12.

* update HOMEPAGE
* drop obsolete patches that source files have been removed
* add dependency efivar
* update CFLAGS to fix print wrong version issue

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>