loongarch: efi: enable generic EFI compressed boot

LoongArch inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5OHOB



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Wire up the generic EFI zboot support for LoongArch64

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>