fbcon: prevent cursor disappearance after switching to 512 character font

Adjust and honor the vc_scrl_erase_char for 256 and 512 character fonts.

It fixes the issue with disappearing cursor during scrolling
(http://bugzilla.kernel.org/show_bug.cgi?id=11258).  The issue was
reported and tracked by Peter Hanzel.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Reported-by: Peter Hanzel <hanzelpeter@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/console/fbcon.c

@@ -2518,7 +2518,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
 			c = vc->vc_video_erase_char;
 			vc->vc_video_erase_char =
 			    ((c & 0xfe00) >> 1) | (c & 0xff);
-			c = vc->vc_def_color;
+			c = vc->vc_scrl_erase_char;
 			vc->vc_scrl_erase_char =
 			    ((c & 0xFE00) >> 1) | (c & 0xFF);
 			vc->vc_attr >>= 1;
@@ -2551,7 +2551,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h,
 			if (vc->vc_can_do_color) {
 				vc->vc_video_erase_char =
 				    ((c & 0xff00) << 1) | (c & 0xff);
-				c = vc->vc_def_color;
+				c = vc->vc_scrl_erase_char;
 				vc->vc_scrl_erase_char =
 				    ((c & 0xFF00) << 1) | (c & 0xFF);
 				vc->vc_attr <<= 1;