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/vexpress_aemv8a_juno_defconfig b/configs/vexpress_aemv8a_juno_defconfig
index 1229601..7b5e4e6 100644
--- a/configs/vexpress_aemv8a_juno_defconfig
+++ b/configs/vexpress_aemv8a_juno_defconfig
@@ -4,6 +4,7 @@
 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_IDENT_STRING=" vexpress_aemv8a"
 CONFIG_DISTRO_DEFAULTS=y
+CONFIG_NR_DRAM_BANKS=2
 CONFIG_BOOTDELAY=1
 CONFIG_USE_BOOTARGS=y
 CONFIG_BOOTARGS="console=ttyAMA0,115200n8 root=/dev/sda2 rw rootwait earlyprintk=pl011,0x7ff80000 debug user_debug=31 androidboot.hardware=juno loglevel=9"