core: Remove redundant else

There is no use for the else phase since when the if condition is true
we already throw an exception.

Change-Id: Idb49270dc895dd38752b1d49a070c4e11d891242
Related to Bug-Url: https://bugzilla.redhat.com/1037441
Signed-off-by: Maor Lipchuk <mlipchuk@redhat.com>