s626: don't dereference insn->data

s626: don't dereference insn->data

`s626_enc_insn_config()` is incorrectly dereferencing `insn->data` which
is a pointer to user memory.  It should be using the separate `data`
parameter that points to a copy of the data in kernel memory.

Note that this insn_config handler is being used incorrectly by this
driver anyway.  `data[0]` should be used to select the type of
configuration being performed, but this driver is treating it as a
counter preload value.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>