$NetBSD: patch-OpenCL.pc.in,v 1.2 2024/04/22 10:43:29 adam Exp $

Link with libpthread in order to unbreak pocl on NetBSD.

--- OpenCL.pc.in.orig	2023-06-02 21:36:20.000000000 +0000
+++ OpenCL.pc.in
@@ -7,4 +7,4 @@ Name: OpenCL
 Description: Open Computing Language generic Installable Client Driver Loader
 Requires: OpenCL-Headers
 Version: @OPENCL_VERSION@
-Libs: -L${libdir} -lOpenCL
+Libs: -L${libdir} -lOpenCL -pthread