cglm requires C11

[barracuda156]

-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/gcc-4.2 - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Configuring done (1.6s)
CMake Error in CMakeLists.txt:
  Target "cglm" requires the language dialect "C11" (with compiler
  extensions).  But the current compiler "GNU" does not support this, or
  CMake does not know the flags to enable it.


CMake Error in CMakeLists.txt:
  Target "cglm" requires the language dialect "C11" (with compiler
  extensions).  But the current compiler "GNU" does not support this, or
  CMake does not know the flags to enable it.


-- Generating done (0.1s)