cmake: bump minimum cmake requirement to 2.8.11
cmake: bump minimum cmake requirement to 2.8.11

commit 43f55fb150ac66498d29f33e5eaa49a1cb456f7e
Author: Emil Velikov <4c996f2f093ddd0585a556460b4cc3ba555546ef@gmail.com>
Date:   Fri Jul 18 14:09:03 2014 +0100

    cmake: rework cmocka build process

Reworked the cmocka build yet it introduced a dependency of
target_include_directories which does not exists in cmake up
until 2.8.11.

Reported-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@gmail.com>
Signed-off-by: Emil Velikov <4c996f2f093ddd0585a556460b4cc3ba555546ef@gmail.com>
Reviewed-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@linux.intel.com>

evelikov/waffle,maurossi/waffle,fjhenigman/waffle,janesma/waffle,dcbaker/waffle,evelikov/waffle,fjhenigman/waffle,chadversary/waffle,maurossi/waffle,dcbaker/waffle,janesma/waffle,waffle-gl/waffle,chadversary/waffle,waffle-gl/waffle,waffle-gl/waffle,maurossi/waffle,fjhenigman/waffle,chadversary/waffle,dcbaker/waffle,janesma/waffle,waffle-gl/waffle,evelikov/waffle