Rename SPL_USB_HOST_SUPPORT to SPL_USB_HOST

Rename this option so that CONFIG_IS_ENABLED can be used with it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/am64x_evm_r5_defconfig b/configs/am64x_evm_r5_defconfig
index 5586786..4e87335 100644
--- a/configs/am64x_evm_r5_defconfig
+++ b/configs/am64x_evm_r5_defconfig
@@ -44,7 +44,7 @@
 CONFIG_SPL_RAM_DEVICE=y
 CONFIG_SPL_REMOTEPROC=y
 CONFIG_SPL_SPI_LOAD=y
-CONFIG_SPL_USB_HOST_SUPPORT=y
+CONFIG_SPL_USB_HOST=y
 CONFIG_SPL_USB_STORAGE=y
 CONFIG_SPL_USB_GADGET=y
 CONFIG_SPL_DFU=y