console-rpc: fix segfault on null stdin
console-rpc: fix segfault on null stdin

If gvir_sandbox_console_attach is called with NULL as the stdin
parameter it results in a segfault in the console-rpc module from
libvirt-sandbox.
Calling with NULL is of course useful when running something
noninteractive and you don't want it to grab the stdin or pass any fd
whatsoever.

commit f94f23314ab654c13bd1e25bd9094f1687fd681a
Author: Radu Caragea <sinaelgl@gmail.com>
Date:   Tue Jun 12 21:31:09 2012 +0300

    Fix crash on null stdin

    When we don't want to run something interactive and we use NULL as the stdin
    the app should still work.

    Signed-off-by: Radu Caragea <sinaelgl@gmail.com>

aristeu/libvirt-sandbox,agx/libvirt-sandbox-debian,erenyagdiran/libvirt-sandbox,libvirt/libvirt-sandbox,erenyagdiran/libvirt-sandbox,kraman/libvirt-sandbox,kraman/libvirt-sandbox,gczarcinski/libvirt-sandbox,agx/libvirt-sandbox-debian,gczarcinski/libvirt-sandbox,gczarcinski/libvirt-sandbox,aristeu/libvirt-sandbox,gczarcinski/libvirt-sandbox,libvirt/libvirt-sandbox,agx/libvirt-sandbox-debian,erenyagdiran/libvirt-sandbox,agx/libvirt-sandbox-debian,aristeu/libvirt-sandbox,aristeu/libvirt-sandbox,erenyagdiran/libvirt-sandbox,kraman/libvirt-sandbox,kraman/libvirt-sandbox,kraman/libvirt-sandbox,kraman/libvirt-sandbox,gczarcinski/libvirt-sandbox,aristeu/libvirt-sandbox,libvirt/libvirt-sandbox,agx/libvirt-sandbox-debian,gczarcinski/libvirt-sandbox