ArmPlatformPkg/Bds: Added boot options reordering

ArmPlatformPkg/Bds: Added boot options reordering

Added the reordering of the boot options feature to the boot manager.
The BootMenuSelectBootOption() has been split into
DisplayBootOptions() that only displays the boot options and
SelectBootOptions() that asks to select one.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Reviewed-By: Olivier Martin <olivier.martin@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15718 6f19259b-4bc3-4df7-8a09-765794883524