Revert "hostfs: Add const qualifier to host_root in hostfs_fill_super()"

This reverts commit 1fbe93dd which is
commit 104eef13 upstream.

It is reported to cause build issues and odds are the root problem isn't
really an issue on the 6.6.y branch anyway.  If it is, someone can
provide a working set of backported patches.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/cd10a924-ae65-4b02-aea2-e629947ca7a3@roeck-us.net


Cc: Hongbo Li <lihongbo22@huawei.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>