uboot-lantiq: mark SPL variants as broken

All SPL variants are lzo compressed. The lzop binary is used for
compression but is not available in tools.

Additionally at least the NAND SPL support is broken and doesn't create
working bootloaders.

The fb3370 SPI NOR SPL enabled u-boot isn't required for LEDE since the
LEDE images are targeting the pre-installed EVA bootloader.

Mark these u-boot variants as well as the SPL variants for the
reference boards as broken till the lzma issues are fixed upstream and
we can use lzma instead of lzo compression.

Signed-off-by: Mathias Kresin <dev@kresin.me>

package/boot/uboot-lantiq/Makefile

@@ -226,6 +226,7 @@ define U-Boot/easy50712_norspl
   BUILD_SUBTARGET:=xway
   BUILD_DEVICES:=EASY50712
   UBOOT_IMAGE:=u-boot.ltq.lzo.norspl
+  DEPENDS+=@BROKEN
 endef
 
 define U-Boot/easy80920_ram
@@ -246,6 +247,7 @@ define U-Boot/easy80920_norspl
   BUILD_SUBTARGET:=xrx200
   BUILD_DEVICES:=EASY80920NOR EASY80920NAND
   UBOOT_IMAGE:=u-boot.ltq.lzo.norspl
+  DEPENDS+=@BROKEN
 endef
 
 define U-Boot/easy80920_sfspl
@@ -253,6 +255,7 @@ define U-Boot/easy80920_sfspl
   BUILD_SUBTARGET:=xrx200
   BUILD_DEVICES:=EASY80920NOR EASY80920NAND
   UBOOT_IMAGE:=u-boot.ltq.lzo.sfspl
+  DEPENDS+=@BROKEN
 endef
 
 define U-Boot/fb3370_eva
@@ -273,6 +276,7 @@ define U-Boot/fb3370_sfspl
   BUILD_SUBTARGET:=xrx200
   BUILD_DEVICES:=FRITZ3370
   UBOOT_IMAGE:=u-boot.ltq.lzo.sfspl
+  DEPENDS+=@BROKEN
 endef
 
 define U-Boot/p2812hnufx_ram
@@ -287,6 +291,7 @@ define U-Boot/p2812hnufx_nandspl
   BUILD_SUBTARGET:=xrx200
   BUILD_DEVICES:=P2812HNUF1
   UBOOT_IMAGE:=u-boot.ltq.lzo.nandspl
+  DEPENDS+=@BROKEN
 endef
 
 define U-Boot/vgv7510kw22_brn