Description: efi/fdt: fix panic when no valid fdt found
References:
Notes:
 carnil> Introduced in b91540d52a08b ("RISC-V: Add EFI runtime services"). Vulnerable
 carnil> versions: 5.10-rc1.
Bugs:
upstream: released (5.13-rc5) [668a84c1bfb2b3fd5a10847825a854d63fac7baa]
6.7-upstream-stable: N/A "Fixed before branching point"
6.6-upstream-stable: N/A "Fixed before branching point"
6.1-upstream-stable: N/A "Fixed before branching point"
5.10-upstream-stable: released (5.10.43) [5148066edbdc89c6fe5bc419c31a5c22e5f83bdb]
4.19-upstream-stable: N/A "Vulnerable code not present"
sid: released (5.10.46-1)
6.1-bookworm-security: N/A "Fixed before branching point"
5.10-bullseye-security: N/A "Fixed before branching point"
4.19-buster-security: N/A "Vulnerable code not present"