configs: am335x_guardian: add ubi fastmap support

- Trigger fastmap automatically

Signed-off-by: Gireesh Hiremath <Gireesh.Hiremath@in.bosch.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20210611161350.2141-4-Gireesh.Hiremath@in.bosch.com

configs/am335x_guardian_defconfig

@@ -87,6 +87,7 @@ CONFIG_SYS_NAND_U_BOOT_LOCATIONS=y
 CONFIG_SYS_NAND_U_BOOT_OFFS=0x100000
 CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND=0x200000
 CONFIG_MTD_UBI_FASTMAP=y
+CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT=1
 CONFIG_PHYLIB=y
 CONFIG_DM_ETH=y
 CONFIG_PHY=y