userportal: Console buttons clickable area fix

[extended userportal]
Console buttons of VMs are clickable on wider area as expected (table cell
where the button is present). This patch fixes this incorrect behavior. Now
the buttons respond when clicking on their area only.

Change-Id: Ib8a0da49e86bc01c73e7a2a7226da773d659a6fc
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=953140
Signed-off-by: Frantisek Kobzik <fkobzik@redhat.com>