Docs: Add missing new line before a list.

llvm-svn: 247360

clang/docs/LanguageExtensions.rst

@@ -1760,6 +1760,7 @@ instructions for implementing atomic operations.
   void __builtin_arm_clrex(void);
 
 The types ``T`` currently supported are:
+
 * Integer types with width at most 64 bits (or 128 bits on AArch64).
 * Floating-point types
 * Pointer types.