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/zipitz2_defconfig b/configs/zipitz2_defconfig
index 935058a..5a5f211 100644
--- a/configs/zipitz2_defconfig
+++ b/configs/zipitz2_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_TARGET_ZIPITZ2=y
 CONFIG_SYS_TEXT_BASE=0x0
+CONFIG_NR_DRAM_BANKS=1
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="console=tty0 console=ttyS2,115200 fbcon=rotate:3"
 # CONFIG_CONSOLE_MUX is not set