Simplify how we keep ATTRs under cursor

Thanks to tarug0 for the suggestion/patch.

x.c

@@ -1266,7 +1266,6 @@ xdrawcursor(void)
 	Glyph g = {' ', ATTR_NULL, defaultbg, defaultcs}, og;
 	int ena_sel = sel.ob.x != -1 && sel.alt == IS_SET(MODE_ALTSCREEN);
 	Color drawcol;
-	unsigned attr;
 
 	LIMIT(oldx, 0, term.col-1);
 	LIMIT(oldy, 0, term.row-1);
@@ -1286,8 +1285,8 @@ xdrawcursor(void)
 	xdrawglyph(og, oldx, oldy);
 
 	g.u = term.line[term.c.y][term.c.x].u;
-	attr = ATTR_BOLD | ATTR_ITALIC | ATTR_UNDERLINE | ATTR_STRUCK;
-	g.mode |= term.line[term.c.y][term.c.x].mode & attr;
+	g.mode |= term.line[term.c.y][term.c.x].mode &
+	          (ATTR_BOLD | ATTR_ITALIC | ATTR_UNDERLINE | ATTR_STRUCK);
 
 	/*
 	 * Select the right color for the right mode.