configs/kontron_bl_imx8mm: U-Boot needs util-linux

Fixes:

/usr/bin/ld: cannot find -lgnutls
/usr/bin/ld: cannot find -luuid
collect2: error: ld returned 1 exit status

when building U-Boot.

Fixes:

  https://gitlab.com/buildroot.org/buildroot/-/jobs/3301821264

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 223516b51e1a45fa86dc1ac959aed93c7434afa4)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/kontron_bl_imx8mm_defconfig

@@ -48,6 +48,7 @@ BR2_TARGET_UBOOT_NEEDS_GNUTLS=y
 BR2_TARGET_UBOOT_NEEDS_ATF_BL31=y
 BR2_TARGET_UBOOT_NEEDS_ATF_BL31_BIN=y
 BR2_TARGET_UBOOT_NEEDS_IMX_FIRMWARE=y
+BR2_TARGET_UBOOT_NEEDS_UTIL_LINUX=y
 BR2_TARGET_UBOOT_FORMAT_CUSTOM=y
 BR2_TARGET_UBOOT_FORMAT_CUSTOM_NAME="flash.bin"
 BR2_TARGET_UBOOT_SPL=y