regulator: qpnp-regulator: Update boost regulator current limit reg address

Update the address used for the boost regulator current limit
register to reflect the correctly location in hardware.  The
proper address is 0x4A, not 0x40.

Change-Id: Ieefcd072858691940103664a2130a6c69341448f
Signed-off-by: David Collins <collinsd@codeaurora.org>