A few more checks for gc.statepoints in the Verifier
A few more checks for gc.statepoints in the Verifier

This is simply a grab bag of unrelated checks:
- A statepoint call can't be marked readonly or readnone
- We don't currently support inline asm or varadic target functions.  Both could be supported, but don't currently work.
- I forgot to check that the number of call arguments actually matched the wrapped callee in my previous change.  Included here.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@223322 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,dslab-epfl/asap,apple/swift-llvm,dslab-epfl/asap,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,dslab-epfl/asap,dslab-epfl/asap,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap