KVM/nVMX: Remove unneeded forward jump in nested_vmx_check_vmentry_hw asm

There is no need to jump just after the jump insn itself. Also, make
code similar to entering guest mode in vmx_vcpu_run.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>