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/syntax.c b/src/syntax.c
index 225853e..56d69c6 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -6970,6 +6970,8 @@
 #ifdef FEAT_GUI
 	"Normal gui=NONE",
 #endif
+	CENT("QuickFixLine term=reverse ctermbg=Cyan",
+	     "QuickFixLine term=reverse ctermbg=Cyan guibg=Cyan"),
 	NULL
     };
 
@@ -7055,6 +7057,8 @@
 	CENT("Conceal ctermbg=DarkGrey ctermfg=LightGrey",
 	     "Conceal ctermbg=DarkGrey ctermfg=LightGrey guibg=DarkGrey guifg=LightGrey"),
 #endif
+	CENT("QuickFixLine term=reverse ctermbg=Cyan",
+	     "QuickFixLine term=reverse ctermbg=Cyan guibg=Cyan"),
 #ifdef FEAT_GUI
 	"Normal gui=NONE",
 #endif