[openwrt/openwrt] uboot-imx: set BUILD_SUBTARGET to 'cortexa9'

[LEDE Commits]

pepe2k pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/b6b09bf00cff38cfc8869053afb3dc26e2150edb

commit b6b09bf00cff38cfc8869053afb3dc26e2150edb
Author: Piotr Dymacz <pepe2k at gmail.com>
AuthorDate: Mon Mar 29 00:48:15 2021 +0200

    uboot-imx: set BUILD_SUBTARGET to 'cortexa9'
    
    All currently supported devices belong to the imx/cortexa9 subtarget.
    
    Signed-off-by: Piotr Dymacz <pepe2k at gmail.com>
---
 package/boot/uboot-imx/Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/package/boot/uboot-imx/Makefile b/package/boot/uboot-imx/Makefile
index 9ca4d55a1c..2faa48bd73 100644
--- a/package/boot/uboot-imx/Makefile
+++ b/package/boot/uboot-imx/Makefile
@@ -24,6 +24,7 @@ define U-Boot/apalis_imx6
   NAME:=Toradex Apalis
   UBOOT_IMAGE:=SPL u-boot.img u-boot-with-spl.imx
   UBOOT_MAKE_FLAGS:=SPL u-boot.img u-boot-with-spl.imx
+  BUILD_SUBTARGET:=cortexa9
   BUILD_DEVICES:=toradex_apalis
 endef
 
@@ -31,11 +32,13 @@ define U-Boot/mx6cuboxi
   NAME:=SolidRun Cubox-i boards
   UBOOT_IMAGE:=SPL u-boot.img
   UBOOT_MAKE_FLAGS:=SPL u-boot.img
+  BUILD_SUBTARGET:=cortexa9
   BUILD_DEVICES:=solidrun_cubox-i
 endef
 
 define U-Boot/wandboard
   NAME:=Wandboard Dual Lite/Quad/Solo
+  BUILD_SUBTARGET:=cortexa9
   BUILD_DEVICES:=wandboard_dual
 endef