intel/clc: allow multiple CL files to be compiled together

v2: use util_dynarray_append() (Jason)
    identation fixes (Jason)

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <mesa/mesa!13171>