leds: qpnp-flash-v2: add delay between LMH mitigation and LED strobe

As per the hardware recommendation, a delay of 500 us is needed
after LMH mitigation is enabled by software and before the flash
LED is strobed. Add it.

Change-Id: Ib70efbb7267510ffb9d95c4aba8566bf6e777c0f
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
diff --git a/drivers/leds/leds-qpnp-flash-v2.c b/drivers/leds/leds-qpnp-flash-v2.c
index 01e553c..b045e3b 100644
--- a/drivers/leds/leds-qpnp-flash-v2.c
+++ b/drivers/leds/leds-qpnp-flash-v2.c
@@ -1077,6 +1077,8 @@
 			pr_err("trigger lmh mitigation failed, rc=%d\n", rc);
 			return rc;
 		}
+		/* Wait for LMH mitigation to take effect */
+		udelay(500);
 	}
 
 	if (led->trigger_chgr) {