target/loongarch: Add loongarch vector property unconditionally

target/loongarch: Add loongarch vector property unconditionally

Currently LSX/LASX vector property is decided by the default value.
Instead vector property should be added unconditionally, and it is
irrelative with its default value. If vector is disabled by default,
vector also can be enabled from command line.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20240521080549.434197-2-maobibo@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>