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/nitrogen6dl2g_defconfig b/configs/nitrogen6dl2g_defconfig
index 378fc24..474ecc0 100644
--- a/configs/nitrogen6dl2g_defconfig
+++ b/configs/nitrogen6dl2g_defconfig
@@ -3,6 +3,7 @@
 CONFIG_SYS_TEXT_BASE=0x17800000
 CONFIG_TARGET_NITROGEN6X=y
 CONFIG_CMD_HDMIDETECT=y
+CONFIG_NR_DRAM_BANKS=1
 CONFIG_SYS_EXTRA_OPTIONS="IMX_CONFIG=board/boundary/nitrogen6x/nitrogen6dl2g.cfg,MX6DL,DDR_MB=2048"
 CONFIG_BOOTDELAY=3
 CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE=y