coral: Enable the copy framebuffer

Enable this feature on chromebook_coral to speed up the display.

With this change, the time taken to print the environment to the display
without CONFIG_CONSOLE_SCROLL_LINES is reduced from 1830ms to 62ms.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

configs/chromebook_coral_defconfig

@@ -95,6 +95,7 @@ CONFIG_TPM2_CR50_I2C=y
 CONFIG_USB_XHCI_HCD=y
 CONFIG_USB_STORAGE=y
 CONFIG_USB_KEYBOARD=y
+CONFIG_VIDEO_COPY=y
 CONFIG_SPL_FS_CBFS=y
 # CONFIG_SPL_USE_TINY_PRINTF is not set
 CONFIG_TPL_USE_TINY_PRINTF=y