Revert "configs/raspberrypi5: install Raspberry Pi 500 device-tree blob"

In Buildroot 2025.02, the vendor specific kernel version used for the
rapsberrypi5 does not yet include any dts named bcm2712-rpi-500.dts, which
results in a build error.

This reverts commit fa0ee12fcc, which was
mistakenly cherry picked regardless of the needed vendor kernel version bump.

Signed-off-by: Titouan Christophe <titouan.christophe@mind.be>

board/raspberrypi/readme.txt

@@ -19,7 +19,6 @@ These instructions apply to all models of the Raspberry Pi:
   - the model CM4 (aka Raspberry Pi Compute Module 4 and IO Board).
   - the model CM4s (aka Raspberry Pi Compute Module 4s).
   - the model B5 (aka Raspberry Pi 5).
-  - the model 500 (aka Raspberry Pi 500).
 
 How to build it
 ===============
@@ -78,7 +77,7 @@ or for CM4 (on IO Board - 64 bit):
 
   $ make raspberrypicm4io_64_defconfig
 
-For model 5 B and 500:
+For model 5 B:
 
   $ make raspberrypi5_defconfig
 
@@ -118,7 +117,6 @@ After building, you should obtain this tree:
     +-- bcm2711-rpi-cm4s.dtb        [1]
     +-- bcm2712-rpi-5-b.dtb         [1]
     +-- bcm2712d0-rpi-5-b.dtb       [1]
-    +-- bcm2712-rpi-500.dtb         [1]
     +-- boot.vfat
     +-- rootfs.ext4
     +-- rpi-firmware/

configs/raspberrypi5_defconfig

@@ -13,7 +13,7 @@ BR2_LINUX_KERNEL_CUSTOM_TARBALL_LOCATION="$(call github,raspberrypi,linux,576cc1
 BR2_LINUX_KERNEL_DEFCONFIG="bcm2712"
 BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="board/raspberrypi/linux-4k-page-size.fragment"
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_INTREE_DTS_NAME="broadcom/bcm2712-rpi-5-b broadcom/bcm2712d0-rpi-5-b broadcom/bcm2712-rpi-500"
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="broadcom/bcm2712-rpi-5-b broadcom/bcm2712d0-rpi-5-b"
 BR2_LINUX_KERNEL_NEEDS_HOST_OPENSSL=y
 BR2_PACKAGE_BUSYBOX_SHOW_OTHERS=y
 BR2_PACKAGE_XZ=y