package/xserver_xorg-server: add version 1.14.7

Some old binary blobs drivers, like the NVidia Tegra2/3 blobs, only
implement an old VIDEODRV ABI.

Since VIDEODRV ABIs are not backward compatible [0], lets introduce an
older Xserver version that supports such an old ABI.

[0] http://www.x.org/wiki/XorgModuleABIVersions/



[Thomas:
  - rename option BR2_PACKAGE_XSERVER_XORG_SERVER_V_1_14_7 to
    BR2_PACKAGE_XSERVER_XORG_SERVER_V_1_14
  - add hash file, change provided by Nicolas Serafini.]

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>