configs: spi: Add the SPI_FLASH_BAR for ESPI

Add the SPI_FLASH_BAR for the ESPI controller of FSL, this entry
is missed by
commit 6d825178 ("configs: Don't use SPI_FLASH_BAR as default")

Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>