glsl: avoid hitting assert for arrays of arrays
glsl: avoid hitting assert for arrays of arrays

Also add TODO comment about adding proper support

Signed-off-by: Timothy Arceri <7f85c8176b2576ffafd04ac63cd29ed35ff86cb6@yahoo.com.au>
Reviewed-by: Ian Romanick <2b237cafb16dc45038e85df6c85e74e6d899eba9@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler