mesa: glGetProgramResourceIndex

Patch adds required helper functions to shaderapi.h and
the actual implementation.

v2: code cleanup (Ilia Mirkin)

corresponding Piglit test:
   arb_program_interface_query-getprogramresourceindex

Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Martin Peres <martin.peres@linux.intel.org>
3 files changed