scons: Do not build glx and egl on Cygwin.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: José Fonseca <jfonseca@vmware.com>

src/SConscript

@@ -22,7 +22,7 @@ SConscript('mesa/SConscript')
 SConscript('mapi/vgapi/SConscript')
 
 if not env['embedded']:
-    if env['platform'] not in ['windows', 'darwin', 'haiku']:
+    if env['platform'] not in ('cygwin', 'darwin', 'haiku', 'windows'):
         SConscript('glx/SConscript')
     if env['platform'] not in ['darwin', 'haiku', 'sunos']:
         SConscript('egl/main/SConscript')

src/gallium/SConscript

@@ -58,7 +58,7 @@ SConscript('winsys/sw/null/SConscript')
 
 if not env['embedded']:
     SConscript('state_trackers/vega/SConscript')
-    if env['platform'] not in ['darwin', 'haiku', 'sunos']:
+    if env['platform'] not in ('cygwin', 'darwin', 'haiku', 'sunos'):
         SConscript('state_trackers/egl/SConscript')
 
     if env['x11']:
@@ -124,7 +124,7 @@ SConscript([
 ])
 
 if not env['embedded']:
-    if env['platform'] not in ['darwin', 'haiku', 'sunos']:
+    if env['platform'] not in ('cygwin', 'darwin', 'haiku', 'sunos'):
         SConscript([
             'targets/egl-static/SConscript'
         ])