Remove remains from cherry pick from LSP branch

Author: Bertik23

llvm/lib/AsmParser/LLLexer.cpp

@@ -198,10 +198,8 @@ const char *LLLexer::skipNChars(unsigned N) {
 
 void LLLexer::advancePositionTo(const char *Ptr) {
   while (CurPtr != Ptr) {
-    // FIXME: Assumes that if moving back, we stay in that line
     if (CurPtr > Ptr) {
       --CurPtr;
-      --CurColNum;
     } else
       getNextChar();
   }