SecurityPkg: Fix one returned code issue in P7Verify Protocol

SecurityPkg: Fix one returned code issue in P7Verify Protocol

VerifyBuffer() in PKCS7 Verify Protocol should return EFI_UNSUPPORTED
when the embedded content is found in SignedData but InData is not NULL.
This patch is to comply with the spec definition.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Qin Long <qin.long@intel.com>
Reviewed-by: Chao Zhang <chao.b.zhang@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18311 6f19259b-4bc3-4df7-8a09-765794883524