leds: qpnp-flash-v2: Fix HW_STROBE configuration

As per the hardware recommendation, configure the LED1 to
HW_STROBE mode when LED2 or LED3 is configured in HW_STROBE
mode. This enables hardware strobe option working for LED2/3
channels.

CRs-Fixed: 2213325
Change-Id: I1ceaa7477b8d0c18e03fbdea9d5347d0e75fc0f0
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>