brcm63xx-arm: Update fake "bcmlinux" Linux kernel for 5.04L.02p1

This kernel is only used for userspace headers. The kernel from the
Broadcom SDK build system is the one ending up in the final image.

Also change to a fixed commit instead of a branch.

Signed-off-by: Andreas Gnau <andreas.gnau@iopsys.eu>

iopsys-brcm63xx-arm/Config.in

@@ -4,8 +4,10 @@ menu "Target options Brcm63xx (ARM)"
 	config KERNEL_GIT_CLONE_URI
 		default "https://dev.iopsys.eu/broadcom/bcmlinux.git" if BRCM_SDK_VER_504021
 
-	config KERNEL_GIT_BRANCH
-		default "bcm_5.04L.02" if BRCM_SDK_VER_504021 # TODO: for now use 5.04L.02 bcmlinux
+        config KERNEL_GIT_BRANCH
+		default "bcm_5.04L.02p1" if BRCM_SDK_VER_504021
+	config KERNEL_GIT_REF
+		default "e6b3646aba036d533e6760aef0f4e1c02208db2d" if BRCM_SDK_VER_504021
 
 	# brcm has it's own brctl
 	config BUSYBOX_DEFAULT_BRCTL