Vlv2TbltDevicePkg: Set CAPSULE_ENABLE to TRUE

Vlv2TbltDevicePkg: Set CAPSULE_ENABLE to TRUE

https://bugzilla.tianocore.org/show_bug.cgi?id=259

Set CAPSULE_ENABLE to TRUE so the standard Vlv2TbltDevicePkg
platform builds can complete.  Build_IFWI.bat assumes this
flag is TRUE.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: David Wei <david.wei@intel.com>
Cc: Mang Guo <mang.guo@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>