Statically link luasession against libreadline

This avoids potential conflicts with system-wide libreadline,
since Ardour binaries no longer need to bundle libreadline.so.

Mainly a workaround for yabridge/wine on recent systems.

luasession/wscript

@@ -8,6 +8,16 @@ def options(opt):
 
 def configure(conf):
     conf.check_cc(
+            msg = 'Checking for static libreadline',
+            header_name='stdio.h readline/readline.h',
+            lib= [':libreadline.a', 'termcap'],
+            uselib_store='READLINE',
+            define_name='HAVE_READLINE',
+            mandatory=False)
+
+    if not conf.is_defined('HAVE_READLINE'):
+        conf.check_cc(
+                msg = 'Checking for libreadline',
                 header_name='stdio.h readline/readline.h',
                 lib='readline',
                 uselib_store='READLINE',