[LibFuzzer] Fix `-Wcomment` warning emitted by GCC.

[delcypher]

Summary

[LibFuzzer] Fix -Wcomment warning emitted by GCC.

./FuzzerIOWindows.cpp:185:1: warning: multi-line comment [-Wcomment]
 // Parse a directory ending in separator, like: SomeDir\
 ^
./FuzzerIOWindows.cpp:200:1: warning: multi-line comment [-Wcomment]
 // Parse a servername and share, like: SomeServer\SomeShare\
 ^

[kcc]

LGTM

llvm/trunk/lib/Fuzzer/FuzzerIOWindows.cpp

 static size_t ParseFileName(const std::string &FileName, const size_t Offset) {
   size_t Pos = Offset;
   const size_t End = FileName.size();
   for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
     ;
   return Pos - Offset;
 }
 
-// Parse a directory ending in separator, like: SomeDir\
+// Parse a directory ending in separator, like: `SomeDir\`
 // Returns number of characters considered if successful.
 static size_t ParseDir(const std::string &FileName, const size_t Offset) {
   size_t Pos = Offset;
   const size_t End = FileName.size();
   if (Pos >= End || IsSeparator(FileName[Pos]))
     return 0;
   for(; Pos < End && !IsSeparator(FileName[Pos]); ++Pos)
     ;
   if (Pos >= End)
     return 0;
   ++Pos; // Include separator.
   return Pos - Offset;
 }
 
-// Parse a servername and share, like: SomeServer\SomeShare\
+// Parse a servername and share, like: `SomeServer\SomeShare\`
 // Returns number of characters considered if successful.
 static size_t ParseServerAndShare(const std::string &FileName,
                                   const size_t Offset) {
   size_t Pos = Offset, Res;
   if (!(Res = ParseDir(FileName, Pos)))
     return 0;
   Pos += Res;
   if (!(Res = ParseDir(FileName, Pos)))