Apple: glFlush() is not needed with CGLFlushDrawable()

<rdar://problem/14496373>

Signed-off-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com>
glsl: Initialize ast_function member variables.

Fixes "Uninitialized pointer field" defect reported by Coverity.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
scons: Don't use -z defs ld option on Mac.

Should fix fdo bug 67098.
llvmpipe: Remove lp_rast_get_num_threads().

Never called.

Trivial.
llvmpipe: Ensure FTZ/DAZ flags are set on deferred draw flushes.

Tested-by: José Fonseca <jfonseca@vmware.com>
build: Add tests directories to SUBDIRS

Fixes a problem with distcheck.
build: Remove unused EGL_PLATFORMS.
egl/build: Remove unused GLAPI_LIB.
configure.ac: Use correct options names in AC_ARG_ENABLE.