targets/opencl: resolve undefined symbols at link time

Current automake build does not try to resolve undefined
symbols thus we could end up with a broken library.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
diff --git a/src/gallium/targets/opencl/Makefile.am b/src/gallium/targets/opencl/Makefile.am
index 7b32a09..a94a518 100644
--- a/src/gallium/targets/opencl/Makefile.am
+++ b/src/gallium/targets/opencl/Makefile.am
@@ -4,6 +4,7 @@
 
 lib@OPENCL_LIBNAME@_la_LDFLAGS = \
 	$(LLVM_LDFLAGS) \
+	-no-undefined \
 	-version-number 1:0
 
 lib@OPENCL_LIBNAME@_la_LIBADD = \