core: Fix missing space in error message
core: Fix missing space in error message

before: "for OpenGL >= 3.2,WAFFLE_CONTEXT_PROFILE must be"
after:  "for OpenGL >= 3.2, WAFFLE_CONTEXT_PROFILE must be"

Signed-off-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@linux.intel.com>

maurossi/waffle,waffle-gl/waffle,chadversary/waffle,evelikov/waffle,fjhenigman/waffle,maurossi/waffle,evelikov/waffle,waffle-gl/waffle,janesma/waffle,yinquan529/waffle-gl-waffle,dcbaker/waffle,dcbaker/waffle,evelikov/waffle,fjhenigman/waffle,waffle-gl/waffle,maurossi/waffle,janesma/waffle,chadversary/waffle,dcbaker/waffle,chadversary/waffle,yinquan529/waffle-gl-waffle,waffle-gl/waffle,yinquan529/waffle-gl-waffle,fjhenigman/waffle,janesma/waffle