omap: Enable PM_RUNTIME in defconfigs to avoid USB compile errors

While waiting for the related USB patch, fix compile by enabling
it in the defconfigs. As discussed at:

http://thread.gmane.org/gmane.linux.usb.general/27432/focus=4460

Otherwise we'll get errors like:

drivers/usb/core/hcd.c:1892: error: 'pm_wq' undeclared (first use in this function)
drivers/usb/core/hcd.c:1892: error: (Each undeclared identifier is reported only once
drivers/usb/core/hcd.c:1892: error: for each function it appears in.)

Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/configs/omap_3430sdp_defconfig b/arch/arm/configs/omap_3430sdp_defconfig
index bb2917e..ddde429 100644
--- a/arch/arm/configs/omap_3430sdp_defconfig
+++ b/arch/arm/configs/omap_3430sdp_defconfig
@@ -363,6 +363,7 @@
 CONFIG_SUSPEND=y
 CONFIG_SUSPEND_FREEZER=y
 # CONFIG_APM_EMULATION is not set
+CONFIG_PM_RUNTIME=y
 CONFIG_ARCH_SUSPEND_POSSIBLE=y
 CONFIG_NET=y