Fix mac build with --with-package-format=dmg

Regression from 7a9f6df7

ERROR: The following errors occurred in packaging process:

ERROR: Source for LICENSE.html not found!
ERROR: Could not copy  to
 /Users/gerrit/lode/bibisect/core63/workdir/installation/LibreOfficeDev/dmg/
install/en-US_inprogress/LibreOfficeDev_6.3.0.0.alpha0_MacOS_x86-64/LICENSEs/LICENSE.html No such file or directory

Change-Id: I6c51a853238b1ecea64f900c0c60e7a9bb370dc9
Reviewed-on: https://gerrit.libreoffice.org/71417
Tested-by: Jenkins
Reviewed-by: Andras Timar <andras.timar@collabora.com>

scp2/source/ooo/scpaction_ooo.scp

@@ -20,8 +20,8 @@
 
 #ifdef MACOSX
 ScpAction scp_Copy_Thirdpartylicense_Readme_Html
-    Copy = "LICENSE.html";
-    Name= "LICENSE.html";
+    Copy = "license.html";
+    Name= "license.html";
     Subdir = "LICENSEs";
 End
 #endif