fbcon: Disallow setting font bigger than screen size

stable inclusion
from stable-v5.10.130
commit b727561ddc9360de9631af2d970d8ffed676a750
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5IQ4M
CVE: CVE-2021-33655

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b727561ddc9360de9631af2d970d8ffed676a750



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commit 65a01e60 upstream.

Prevent that users set a font size which is bigger than the physical screen.
It's unlikely this may happen (because screens are usually much larger than the
fonts and each font char is limited to 32x32 pixels), but it may happen on
smaller screens/LCD displays.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>