SecurityPkg/SecurityPkg.dec: Update TcgPpVendorLib.h to Tcg2PpVendorLib.h

SecurityPkg/SecurityPkg.dec: Update TcgPpVendorLib.h to Tcg2PpVendorLib.h

Tcg2PpVendorLib library class header should be
Include/Library/Tcg2PpVendorLib.h instead of
Include/Library/TcgPpVendorLib.h.
https://bugzilla.tianocore.org/show_bug.cgi?id=2146

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian Wang <jian.j.wang@intel.com>
Cc: Chao Zhang <chao.b.zhang@intel.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Chao Zhang <chao.b.zhang@intel.com>