cmake: Enable process_vm_readv detection on android
cmake: Enable process_vm_readv detection on android

Only android and linux can have this function as far as I am aware, but
it seems cleaner to enable this code for all platforms.

git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@304405 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb