configs: Migrate CONFIG_NR_DRAM_BANKS

We have the following cases:
- CONFIG_NR_DRAM_BANKS was defined, migrate normally
- CONFIG_NR_DRAM_BANKS_MAX was defined and then used for
  CONFIG_NR_DRAM_BANKS after a check, just migrate it over now.
- CONFIG_NR_DRAM_BANKS was very oddly defined on p2771-0000-* (to 1024 +
  2), set this to 8.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/opos6uldev_defconfig b/configs/opos6uldev_defconfig
index 729f9d7..f3b14e4 100644
--- a/configs/opos6uldev_defconfig
+++ b/configs/opos6uldev_defconfig
@@ -13,6 +13,7 @@
 CONFIG_SPL_LIBDISK_SUPPORT=y
 # CONFIG_CMD_BMODE is not set
 CONFIG_DEFAULT_DEVICE_TREE="imx6ul-opos6uldev"
+CONFIG_NR_DRAM_BANKS=1
 CONFIG_TPL_SYS_MALLOC_F_LEN=0x400
 CONFIG_BOOTDELAY=5
 CONFIG_USE_BOOTARGS=y