Fixes tags need work in the iio-fixes tree

In commit

55bf748e4e1e ("iio: adc: mt6359: fix unchecked return value in mt6358_read_imp")

Fixes tag

has these problem(s):

- SHA1 should be at least 12 digits long
This can be fixed for the future by setting core.abbrev to 12 (or more) or (for git v2.11 or later) just making sure it is not set (or set to "auto").