NetworkPkg/Ip6Dxe: Uninstall protocols when error happen in Driver Binding Start.

NetworkPkg/Ip6Dxe: Uninstall protocols when error happen in Driver Binding Start.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1447

This patch is to uninstall Ip6ServiceBindingProtocol and Ip6ConfigProtocol when
error happen in Driver Binding Start.

Cc: Michael Turner <Michael.Turner@microsoft.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
Signed-off-by: Michael Turner <Michael.Turner@microsoft.com>
Reviewed-By: Ye Ting <ting.ye@intel.com>