x86: Enable DM_USB for link and panther

Move these two boards to use driver model for USB.

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

configs/chromebook_link_defconfig

@@ -37,6 +37,8 @@ CONFIG_SYS_NS16550=y
 CONFIG_ICH_SPI=y
 CONFIG_TIMER=y
 CONFIG_TPM_TIS_LPC=y
+CONFIG_USB=y
+CONFIG_DM_USB=y
 CONFIG_VIDEO_VESA=y
 CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
 CONFIG_FRAMEBUFFER_VESA_MODE_11A=y

configs/chromebox_panther_defconfig

@@ -29,6 +29,8 @@ CONFIG_SYS_NS16550=y
 CONFIG_ICH_SPI=y
 CONFIG_TIMER=y
 CONFIG_TPM_TIS_LPC=y
+CONFIG_USB=y
+CONFIG_DM_USB=y
 CONFIG_VIDEO_VESA=y
 CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
 CONFIG_FRAMEBUFFER_VESA_MODE_11A=y