hwmon: qpnp-adc: Fix key not in data bug

The sysfs attribute is initialized properly, but the
initialization is overwritten by the memcpy directly following
that line. Do the initialization after the memcpy to avoid the

	BUG: key eeb16158 not in .data!

warnings from lockdep.

Change-Id: I9ff7f750a29b637348aa4fbd1a17bc5c2cfb1302
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>