configs: change bpi-r3 to board specific dts and change prompt

Use own devicetree for the board and change the prompt.

Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
diff --git a/configs/mt7986a_bpir3_sd_defconfig b/configs/mt7986a_bpir3_sd_defconfig
index 08edfe7..36547db 100644
--- a/configs/mt7986a_bpir3_sd_defconfig
+++ b/configs/mt7986a_bpir3_sd_defconfig
@@ -7,15 +7,15 @@
 CONFIG_NR_DRAM_BANKS=1
 CONFIG_ENV_SIZE=0x80000
 CONFIG_ENV_OFFSET=0x300000
-CONFIG_DEFAULT_DEVICE_TREE="mt7986a-sd-rfb"
-CONFIG_SYS_PROMPT="MT7986> "
+CONFIG_DEFAULT_DEVICE_TREE="mt7986a-bpi-r3-sd"
+CONFIG_SYS_PROMPT="BPI-R3> "
 CONFIG_TARGET_MT7986=y
 CONFIG_DEBUG_UART_BASE=0x11002000
 CONFIG_DEBUG_UART_CLOCK=40000000
 CONFIG_SYS_LOAD_ADDR=0x46000000
 CONFIG_DEBUG_UART=y
 # CONFIG_AUTOBOOT is not set
-CONFIG_DEFAULT_FDT_FILE="mt7986a-sd-rfb"
+CONFIG_DEFAULT_FDT_FILE="mt7986a-bpi-r3-sd"
 CONFIG_LOGLEVEL=7
 CONFIG_LOG=y
 CONFIG_SYS_CBSIZE=512