configs: rpi: set NR_DRAM_BANKS to four

With the new RPi4 which has 8 GB of RAM, we can have up to four DRAM
banks. Bump up the configuration files to detect all the memory in
U-Boot.

Signed-off-by: Matthias Brugger <mbrugger@suse.com>
diff --git a/configs/rpi_4_32b_defconfig b/configs/rpi_4_32b_defconfig
index b22316c..f369bb9 100644
--- a/configs/rpi_4_32b_defconfig
+++ b/configs/rpi_4_32b_defconfig
@@ -4,7 +4,7 @@
 CONFIG_TARGET_RPI_4_32B=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_ENV_SIZE=0x4000
-CONFIG_NR_DRAM_BANKS=2
+CONFIG_NR_DRAM_BANKS=4
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_ARCH_FIXUP_FDT_MEMORY=y
diff --git a/configs/rpi_4_defconfig b/configs/rpi_4_defconfig
index 0759805..d4b586c 100644
--- a/configs/rpi_4_defconfig
+++ b/configs/rpi_4_defconfig
@@ -4,7 +4,7 @@
 CONFIG_TARGET_RPI_4=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_ENV_SIZE=0x4000
-CONFIG_NR_DRAM_BANKS=2
+CONFIG_NR_DRAM_BANKS=4
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_ARCH_FIXUP_FDT_MEMORY=y
diff --git a/configs/rpi_arm64_defconfig b/configs/rpi_arm64_defconfig
index 66c4a53..f8a369f 100644
--- a/configs/rpi_arm64_defconfig
+++ b/configs/rpi_arm64_defconfig
@@ -4,7 +4,7 @@
 CONFIG_TARGET_RPI_ARM64=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000
 CONFIG_ENV_SIZE=0x4000
-CONFIG_NR_DRAM_BANKS=2
+CONFIG_NR_DRAM_BANKS=4
 CONFIG_DISTRO_DEFAULTS=y
 CONFIG_OF_BOARD_SETUP=y
 CONFIG_USE_PREBOOT=y