Capability attributes can now be declared on a typedef declaration as well as a struc...

Capability attributes can now be declared on a typedef declaration as well as a structure declaration. This allows for C code to use Boolean expressions on a capability as part of another attribute. Eg) __attribute__((requires_capability(!SomeCapability)))

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@204657 91177308-0d34-0410-b5e6-96231b3b80d8