omap: switch to kernel 5.4

Runtime tested on beagleblack.

Signed-off-by: Andre Heider <a.heider@gmail.com>
[added test comment]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

target/linux/omap/Makefile

@@ -14,7 +14,7 @@ FEATURES:=usb usbgadget ext4 targz fpu audio display nand squashfs
 CPU_TYPE:=cortex-a8
 CPU_SUBTYPE:=vfpv3
 
-KERNEL_PATCHVER:=4.19
+KERNEL_PATCHVER:=5.4
 
 KERNELNAME:=zImage dtbs