patch 8.0.0641: cannot set a separate highlighting for the quickfix line

Problem:    Cannot set a separate highlighting for the current line in the
            quickfix window.
Solution:   Add QuickFixLine. (anishsane, closes #1755)
diff --git a/src/option.c b/src/option.c
index f9d2734..2a92bc5 100644
--- a/src/option.c
+++ b/src/option.c
@@ -476,8 +476,9 @@
 /* Make the string as short as possible when compiling with few features. */
 #if defined(FEAT_DIFF) || defined(FEAT_FOLDING) || defined(FEAT_SPELL) \
 	|| defined(FEAT_WINDOWS) || defined(FEAT_CLIPBOARD) \
-	|| defined(FEAT_INS_EXPAND) || defined(FEAT_SYN_HL) || defined(FEAT_CONCEAL)
-# define HIGHLIGHT_INIT "8:SpecialKey,~:EndOfBuffer,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,N:CursorLineNr,r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title,v:Visual,V:VisualNOS,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn,A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn,-:Conceal,B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel,x:PmenuSbar,X:PmenuThumb,*:TabLine,#:TabLineSel,_:TabLineFill,!:CursorColumn,.:CursorLine,o:ColorColumn"
+	|| defined(FEAT_INS_EXPAND) || defined(FEAT_SYN_HL) \
+	|| defined(FEAT_CONCEAL) || defined(FEAT_QUICKFIX)
+# define HIGHLIGHT_INIT "8:SpecialKey,~:EndOfBuffer,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,N:CursorLineNr,r:Question,s:StatusLine,S:StatusLineNC,c:VertSplit,t:Title,v:Visual,V:VisualNOS,w:WarningMsg,W:WildMenu,f:Folded,F:FoldColumn,A:DiffAdd,C:DiffChange,D:DiffDelete,T:DiffText,>:SignColumn,-:Conceal,B:SpellBad,P:SpellCap,R:SpellRare,L:SpellLocal,+:Pmenu,=:PmenuSel,x:PmenuSbar,X:PmenuThumb,*:TabLine,#:TabLineSel,_:TabLineFill,!:CursorColumn,.:CursorLine,o:ColorColumn,q:QuickFixLine"
 #else
 # define HIGHLIGHT_INIT "8:SpecialKey,@:NonText,d:Directory,e:ErrorMsg,i:IncSearch,l:Search,m:MoreMsg,M:ModeMsg,n:LineNr,N:CursorLineNr,r:Question,s:StatusLine,S:StatusLineNC,t:Title,v:Visual,w:WarningMsg,W:WildMenu,>:SignColumn,*:TabLine,#:TabLineSel,_:TabLineFill"
 #endif