int befs_nls2utf (struct super_block * sb, const char * in, int in_len, char ** out, int * out_len);
Converts input string src, which is in the format of the loaded NLS map, into a utf8 string.
The destination string dest is allocated by this function and the caller is responsible for freeing it with kfree
On return, *destlen is the length of dest in bytes.
On success, the return value is the number of utf8 characters written to the output buffer dest.
On Failure, a negative number coresponding to the error code is returned.