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/porter_defconfig b/configs/porter_defconfig
index 6efa641..363a502 100644
--- a/configs/porter_defconfig
+++ b/configs/porter_defconfig
@@ -16,6 +16,7 @@
 CONFIG_SPL_SPI_FLASH_SUPPORT=y
 CONFIG_SPL_SPI_SUPPORT=y
 CONFIG_DEFAULT_DEVICE_TREE="r8a7791-porter-u-boot"
+CONFIG_NR_DRAM_BANKS=1
 CONFIG_FIT=y
 CONFIG_BOOTDELAY=3
 CONFIG_VERSION_VARIABLE=y