build: switch preliminary LGPL mode from v3 to v2.1

iive agreed to relicense things that are still in mpv to LGPLv2.1. So
change the licenses of the affected files, and rename the configure
switch for LGPL mode to --enable-preliminary-lgpl2.

(The "preliminary" part will probably be removed from the configure
switch soon as well.)

Also player/main.c hasn't had GPL parts since a few commits ago.

1 files changed, 3 insertions, 3 deletions

diff --git a/wscript b/wscript
index 941131cf4c..107db6ca50 100644
--- a/wscript
+++ b/wscript
@@ -27,14 +27,14 @@ Dependency identifiers (for win32 vs. Unix):
 
 build_options = [
     {
-        'name': '--preliminary-lgpl3',
-        'desc': 'Preliminary LGPLv3+ license',
+        'name': '--preliminary-lgpl2',
+        'desc': 'Preliminary LGPLv2.1+ license',
         'default': 'disable',
         'func': check_true,
     }, {
         'name': 'gpl',
         'desc': 'GPL build',
-        'deps': '!preliminary-lgpl3',
+        'deps': '!preliminary-lgpl2',
         'func': check_true,
     }, {
         'name': 'libaf',