spmi: pmic-arb: Use asynchronous probe

A spmi controller may have many child devices, which together may take
a signifigant amount of time to register and probe. Reduce this effect
by probing asynchronously.

After:
[    0.277217] calling__software_resume+0x0/0x24c_@_1
Before:
[    0.319295] calling__software_resume+0x0/0x24c_@_1

Change-Id: I95704a2ae7aae98e23dc9f29c7d023867d60388d
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>
diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c
index 6199523..0f0b7ba 100644
--- a/drivers/spmi/spmi-pmic-arb.c
+++ b/drivers/spmi/spmi-pmic-arb.c
@@ -1449,6 +1449,7 @@
 	.driver		= {
 		.name	= "spmi_pmic_arb",
 		.of_match_table = spmi_pmic_arb_match_table,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},
 };