hw/loongarch: Refine fwcfg memory map

hw/loongarch: Refine fwcfg memory map

Memory map table for fwcfg is used for UEFI BIOS, UEFI BIOS uses the first
entry from fwcfg memory map as the first memory HOB, the second memory HOB
will be used if the first memory HOB is used up.

Memory map table for fwcfg does not care about numa node, however in
generic the first memory HOB is part of numa node0, so that runtime
memory of UEFI which is allocated from the first memory HOB is located
at numa node0.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240515093927.3453674-4-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>