md: revert incorrect fix for read error handling in raid1.
commit 4706b349 was a forward port of a fix that was needed for SLES10. But in fact it is not needed in mainline because the earlier commit dd00a99e fixes the same problem in a better way. Further, this commit introduces a bug in the way it interacts with the automatic read-error-correction. If, after a read error is successfully corrected, the same disk is chosen to re-read - the re-read won't be attempted but an error will be returned instead. After reverting that commit, there is the possibility that a read error on a read-only array (where read errors cannot be corrected as that requires a write) will repeatedly read the same device and continue to get an error. So in the "Array is readonly" case, fail the drive immediately on a read error. Signed-off-by: NeilBrown <firstname.lastname@example.org> Cc: email@example.com