leds: leds-qpnp: set VREG_OK parameter based on strobe type

If the strobe is from hardware, vreg_ok parameter is set to
0x40 and if the strobe is from software, vreg_ok parameter
is set to 0x80.

Change-Id: Ic692bee1e40c3ee0d69e319bf80cb8b135d6833c
Signed-off-by: Abinaya P <abinayap@codeaurora.org>