udisks2: set timeout to INTMAX when unmounting a filesystem
udisks2: set timeout to INTMAX when unmounting a filesystem

It may indeed take more than 25 seconds if there's a lot of data to
write. Related to https://bugzilla.redhat.com/show_bug.cgi?id=819492

Signed-off-by: David Zeuthen <16a4bae6a7afea1fdd75baca6404fe68f285db96@redhat.com>

philipl/gvfs,gicmo/gvfs,halfline/gvfs,xkahn/gvfs-cmis,philipl/gvfs,gicmo/gvfs,halfline/gvfs,gicmo/gvfs,xkahn/gvfs-cmis,xkahn/gvfs-cmis,xkahn/gvfs-cmis,philipl/gvfs,gicmo/gvfs,halfline/gvfs