regulator: qpnp-regulator: fix qpnp_print_actions const usage

The const keyword is not being used correctly for the
qpnp_print_actions array in qpnp-regulator.c.  The array pointer
itself should be specified as const as well.

Change-Id: I0d6f2323d3add646696a7d1453cb58300258c215
Signed-off-by: David Collins <collinsd@codeaurora.org>