Fix a bug which hangs build if FV section only has attributes listed.

Reviewed-by: Hesheng Chen <hesheng.chen@intel.com>
Signed-off-by: Yingke Liu <yingke.d.liu@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2-buildtools/code/trunk/BaseTools@2609 c2973edb-eda0-4c78-bc6a-9341b269661f
Enable PCD External Database, Sku and PcdInfo feature.
Signed-off-by: Feng, Bob C <bob.c.feng@intel.com>
Reviewed-by: Liu, Yingke D <yingke.d.liu@intel.com> 
Reviewed-by: Liu, Jiang A jiang.a.liu@intel.com

git-svn-id: https://svn.code.sf.net/p/edk2-buildtools/code/trunk/BaseTools@2610 c2973edb-eda0-4c78-bc6a-9341b269661f