x86: Convert minnowmax to use CONFIG_DM_USB

Move to driver model for USB on minnowmax.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

configs/minnowmax_defconfig

@@ -18,13 +18,14 @@ CONFIG_OF_CONTROL=y
 CONFIG_CPU=y
 CONFIG_DM_PCI=y
 CONFIG_SPI_FLASH=y
+CONFIG_DEBUG_UART=y
+CONFIG_DEBUG_UART_BASE=0x3f8
+CONFIG_DEBUG_UART_CLOCK=1843200
 CONFIG_VIDEO_VESA=y
 CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
 CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
+CONFIG_USB=y
+CONFIG_DM_USB=y
 CONFIG_DM_RTC=y
 CONFIG_USE_PRIVATE_LIBGCC=y
 CONFIG_SYS_VSNPRINTF=y
-CONFIG_DEBUG_UART=y
-CONFIG_DEBUG_UART_NS16550=y
-CONFIG_DEBUG_UART_BASE=0x3f8
-CONFIG_DEBUG_UART_CLOCK=1843200