ipq807x: force ext4 creation in emmc_do_upgrade

Running mkfs.ext4 on a partition that already contains an ext4
filesystem asks for input:

  mke2fs 1.45.6 (20-Mar-2020)
  /dev/mmcblk0p9 contains a ext4 file system
          created on Sat Jun 11 12:23:42 2022
  Proceed anyway? (y,N) y

This breaks the ability to run sysupgrade non-interactively. Add the -F
switch to force ext4 creation to fix this.

Fixes: WIFI-9419
Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>

feeds/ipq807x/ipq807x/base-files/lib/upgrade/platform.sh

@@ -59,7 +59,7 @@ emmc_do_upgrade() {
 
 	local emmcblock="$(find_mmc_part "rootfs_data")"
         if [ -e "$emmcblock" ]; then
-                mkfs.ext4 "$emmcblock"
+                mkfs.ext4 -F "$emmcblock"
         fi
 }