Maintainers.txt: Update EDK II Releases to EDK-II-Release-Planning wiki
Maintainers.txt: Update EDK II Releases to EDK-II-Release-Planning wiki

In V2, add Liming Gao as the maintainer of EDK II Releases.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <6480311aeeb4b006862f6d13ebabddc03f51e507@intel.com>
Cc: Laszlo Ersek <7437296077edea1cb64451c122c4dac071f0cfbc@redhat.com>
Reviewed-by: Laszlo Ersek <7437296077edea1cb64451c122c4dac071f0cfbc@redhat.com>

MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2