Revert "nfs: clear SB_RDONLY before getting superblock"

Revert "nfs: clear SB_RDONLY before getting superblock"

[ Upstream commit d216b698d44e33417ad4cc796cb04ccddbb8c0ee ]

This reverts commit 8cd9b785943c57a136536250da80ba1eb6f8eb18.

Silently ignoring the "ro" and "rw" mount options causes user confusion,
and regressions.

Reported-by: Alkis Georgopoulos<alkisg@gmail.com>
Cc: Li Lingfeng <lilingfeng3@huawei.com>
Fixes: 8cd9b785943c ("nfs: clear SB_RDONLY before getting superblock")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>