Update year in license files

In last year's update (D48219) it was suggested that the release manager
might want to do this, so here we go.

llvm-svn: 351194
GitOrigin-RevId: eb60fbfdb43cb8583eda1e338b3489ddef332f10
1 file changed
tree: 151ad27ec3c8a2c0f6c20cfc6424c2e63ce7d70f
  1. LICENSE.TXT