Hisilicon: drop unused VirtualRealTimeClockLib instance

VirtualRealTimeClockLib is not used in either edk2-platforms or
edk2-non-osi, and there never has been a reference to it -- even the
initial code drop that added it to edk2-platforms [*] contained zero
references to it. Remove it.

[*] commit 600081b5 ("Platform,Silicon: Import Hisilicon D02,D03,D05
and HiKey", 2017-08-03)

Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Wenyi Xie <xiewenyi2@huawei.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=4564


Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>