account for OpenBSD

Index: tests/egl/CMakeLists.gl.txt
--- tests/egl/CMakeLists.gl.txt.orig
+++ tests/egl/CMakeLists.gl.txt
@@ -10,7 +10,7 @@ link_libraries (
 	${OPENGL_gl_LIBRARY}
 )
 
-IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD")
 	piglit_add_executable (egl-nok-swap-region egl-util.c egl-nok-swap-region.c)
 	target_link_libraries(egl-nok-swap-region pthread ${X11_X11_LIB})
 	piglit_add_executable (egl-nok-texture-from-pixmap egl-util.c egl-nok-texture-from-pixmap.c)
@@ -35,6 +35,6 @@ IF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
 	target_link_libraries(egl-invalid-attr pthread)
 	piglit_add_executable (egl-context-priority egl-context-priority.c)
 	target_link_libraries(egl-context-priority pthread)
-ENDIF(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
+ENDIF(${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD")
 
 # vim: ft=cmake:
