matvecmult's opencl kernel is from NVIDIA with odd license.

--- a/examples/Makefile.am.orig	2012-01-25 14:55:15.650758414 +0100
+++ b/examples/Makefile.am	2012-01-25 14:55:18.718696978 +0100
@@ -702,10 +702,12 @@
 # matVecMult example #
 ######################
 
+if FALSE
 if STARPU_USE_OPENCL
 nobase_STARPU_OPENCL_DATA_DATA += \
 	matvecmult/matvecmult_kernel.cl
 endif
+endif
 
 #######################
 # dot_product example #
