linux: select host-uboot-tools on nios2

In the latest kernel, U-Boot images are always generated when building
a kernel for NIOS2. Note that we build the kernel with:

  make all
  make <selected-image>

so the selected image through Buildroot options doesn't matter: a
U-Boot image is always generated.

Therefore, in order to fix autobuilder issues, make sure
host-uboot-tools are always selected when building the latest kernel
version. We do not select it in general as custom versions may be
different.

Fixes:

  http://autobuild.buildroot.net/results/1d4c249887bdd78dab40152ad3a4fcef16458a1a/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

linux/Config.in

@@ -33,6 +33,8 @@ config BR2_LINUX_KERNEL_LATEST_VERSION
 	# mips always generates an ITB image
 	select BR2_PACKAGE_HOST_UBOOT_TOOLS if BR2_mips || BR2_mipsel || BR2_mips64 || BR2_mips64el
 	select BR2_PACKAGE_HOST_UBOOT_TOOLS_FIT_SUPPORT if BR2_mips || BR2_mipsel || BR2_mips64 || BR2_mips64el
+	# nios2 always generates a U-Boot image
+	select BR2_PACKAGE_HOST_UBOOT_TOOLS if BR2_nios2
 
 config BR2_LINUX_KERNEL_LATEST_CIP_VERSION
 	bool "Latest CIP SLTS version (5.10.162-cip24)"