configs: get rid of build warnings due to SPL_USB_DWC3_GENERIC

Adding the SPL_USB_DWC3_GENERIC symbol broke some ti builds. This
should fix the builds but untested on HW.

Signed-off-by: Angus Ainslie <angus@akkea.ca>
diff --git a/configs/am43xx_evm_usbhost_boot_defconfig b/configs/am43xx_evm_usbhost_boot_defconfig
index 0a4b9a9..8acf06d 100644
--- a/configs/am43xx_evm_usbhost_boot_defconfig
+++ b/configs/am43xx_evm_usbhost_boot_defconfig
@@ -8,6 +8,7 @@
 CONFIG_DEFAULT_DEVICE_TREE="am437x-gp-evm"
 CONFIG_AM43XX=y
 CONFIG_SPL=y
+CONFIG_SPL_MISC=y
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
 CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x4033ff00
@@ -104,6 +105,7 @@
 CONFIG_USB_DWC3=y
 CONFIG_USB_DWC3_OMAP=y
 CONFIG_USB_DWC3_GENERIC=y
+CONFIG_SPL_USB_DWC3_GENERIC=y
 CONFIG_USB_DWC3_PHY_OMAP=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_GADGET_MANUFACTURER="Texas Instruments"