Replace APFloatBase static fltSemantics data members with getter functions

At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
diff --git a/clang-tools-extra/clang-tidy/misc/IncorrectRoundings.cpp b/clang-tools-extra/clang-tidy/misc/IncorrectRoundings.cpp
index b7c8e0a..7f9b90b 100644
--- a/clang-tools-extra/clang-tidy/misc/IncorrectRoundings.cpp
+++ b/clang-tools-extra/clang-tidy/misc/IncorrectRoundings.cpp
@@ -23,9 +23,9 @@
 namespace {
 AST_MATCHER(FloatingLiteral, floatHalf) {
   const auto &literal = Node.getValue();
-  if ((&Node.getSemantics()) == &llvm::APFloat::IEEEsingle)
+  if ((&Node.getSemantics()) == &llvm::APFloat::IEEEsingle())
     return literal.convertToFloat() == 0.5f;
-  if ((&Node.getSemantics()) == &llvm::APFloat::IEEEdouble)
+  if ((&Node.getSemantics()) == &llvm::APFloat::IEEEdouble())
     return literal.convertToDouble() == 0.5;
   return false;
 }