Fix typos throughout the license files that somehow I and my reviewers all missed!
Fix typos throughout the license files that somehow I and my reviewers
all missed!

Thanks to Alex Bradbury for pointing this out, and the fact that I never
added the intended `legacy` anchor to the developer policy. Add that
anchor too. With hope, this will cause the links to all resolve
successfully.

git-svn-id: 62ef012455b6b8fcec9c41ca270ebf409aae1006@351731 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/libunwind,llvm-mirror/libunwind,llvm-mirror/libunwind