FROMLIST: Revert "fuse: Apply flags2 only when userspace set the FUSE_INIT_EXT"

This reverts commit 3066ff93.

This patch breaks all existing userspace by requiring updates as
mentioned in the commit message, which is not allowed.

Revert to restore compatibility with existing userspace
implementations.

Cc: Bernd Schubert <bschubert@ddn.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Test: TH
Bug: 298946207
Link: https://lore.kernel.org/all/20230904133321.104584-1-git@andred.net/


Change-Id: I853761625a57d3259252d5eb695828b35ed40b4d
Signed-off-by: André Draszik <draszik@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>