target/i386: sev: Remove redundant handle field

target/i386: sev: Remove redundant handle field

The user can explicitly specify a handle via the "handle" property wired
to SevGuestState::handle.  That gets passed to the KVM_SEV_LAUNCH_START
ioctl() which may update it, the final value being copied back to both
SevGuestState::handle and SEVState::handle.

AFAICT, nothing will be looking SEVState::handle before it and
SevGuestState::handle have been updated from the ioctl().  So, remove the
field and just use SevGuestState::handle directly.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200604064219.436242-9-david@gibson.dropbear.id.au>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>