Add LoongArch's vector extensions support, which including
128bit LSX (i.e., Loongson SIMD eXtension) and 256bit LASX
(i.e., Loongson Advanced SIMD eXtension). This patch support
gdb to fetch/store vector registers.
Signed-off-by: Hui Li <lihui@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
