ArmVirtualizationPkg: FdtPL011SerialPortLib: support UEFI_APPLICATION

The library already supports UEFI_DRIVER, we just need to relax the
restriction list.

This allows ArmVirtualizationPkg platforms to build applications, like the
UEFI shell.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-By:  Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16219 6f19259b-4bc3-4df7-8a09-765794883524