mtd: fix callback return value check
mtd: fix callback return value check

Drivers may (and do) return negative errno values other than -1 from the
ecc.correct callback.

Signed-off-by: Baruch Siach <53ccad33e0625915318fb3bc832e5c1c413d1294@tkos.co.il>
Signed-off-by: Artem Bityutskiy <19b5733dcea388885746d36043d3568bba5b4df7@nokia.com>
Signed-off-by: David Woodhouse <b460d66aaf00c296a3db1c1d9eeafc081d5f7d70@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas