ASTBridging: fix storage size of BridgedDiagnosticFixIt

and fix the static_assert error message

Author: eeckstein

include/swift/AST/ASTBridging.h

@@ -67,7 +67,7 @@ class BridgedDiagnosticArgument {
 };
 
 class BridgedDiagnosticFixIt {
-  int64_t storage[6];
+  int64_t storage[7];
 
 public:
 #ifdef USED_IN_CPP_SOURCE

lib/AST/ASTBridging.cpp

@@ -35,7 +35,7 @@ BridgedDiagnosticArgument::BridgedDiagnosticArgument(BridgedStringRef s)
   : BridgedDiagnosticArgument(DiagnosticArgument(s.get())) {}
 
 static_assert(sizeof(BridgedDiagnosticFixIt) >= sizeof(DiagnosticInfo::FixIt),
-              "BridgedDiagnosticArgument has wrong size");
+              "BridgedDiagnosticFixIt has wrong size");
 
 static SourceLoc getSourceLoc(BridgedSourceLoc bridgedLoc) {
   return SourceLoc(llvm::SMLoc::getFromPointer(bridgedLoc.getLoc()));