sql: don't uppercase name of binary collation

Since now we don't have real binary collation, it was allowed to use its
name in different cases. For instance: BiNaRY, "bInArY", "BINARY" etc.
All these names were valid and accounted for binary collation.
However, we are going to introduce real entry in _collation space to
represent binary collation. Thus, for now we allow using only standard
"binary" name.

Needed for #3185