target-i386: kvm: do not initialize padding fields

target-i386: kvm: do not initialize padding fields

The exception.pad field is going to be renamed to pending in an upcoming
header file update.  Remove the unnecessary initialization; it was
introduced to please valgrind (commit 7e680753cfa2) but they were later
rendered unnecessary by commit 076796f8fd27f4d, which added the "= {}"
initializer to the declaration of "events".  Therefore the patch does
not change behavior in any way.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>