Fixes build failure:
build.py...
/home/kraxel/projects/edk2/OvmfPkg/Bhyve/BhyveX64.dsc(...): error 1001: Module type [SEC] is not supported by library instance [/home/kraxel/projects/edk2/OvmfPkg/Library/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf]
consumed by [/home/kraxel/projects/edk2/OvmfPkg/Sec/SecMain.inf]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>