Removed hotfix proposed in bnc#798620.

The hotfix was partially responsible for incomplete firewall initialization
after second stage. Firewall initialization has two phases, which are
invoked by two services:
* SuSEfirewall_init.service (phase 1)
* SuSEfirewall.serive (phase 2)
The hotfix blocked second phase from starting after second stage, so the
firewall stayed in close state.

However to get things working properly a fix is required for
SuSEFirewall yast module as well. It must not start second phase during
installation (it deadlocks systemd).

Eventually, a fix in above mentioned service files is needed. Those
files belongs to SuSEfirewall2.rpm. The fix is present in
http://gitorious.org/opensuse/susefirewall2 commit: 390d164e. However,
it wasn't released for 13.1 (Milestone4 in time of writting).
Updated changelog.
Updated spec.
Merge pull request #66 from mchf/master

Removed hotfix which could cause an issue when starting firewall after second stage.