sunxi: add testing 5.4 kernel

Add 5.4 as testing kernel.

Signed-off-by: Aleksander Jan Bajkowski <[email protected]>

target/linux/sunxi/Makefile

@@ -15,6 +15,7 @@ SUBTARGETS:=cortexa8 cortexa7 cortexa53
 MAINTAINER:=Zoltan HERPAI <[email protected]>
 
 KERNEL_PATCHVER:=4.19
+KERNEL_TESTING_PATCHVER:=5.4
 KERNELNAME:=zImage dtbs
 
 # A10: Cortex-A8