loongarch support

[junchao-loongson]

test info:

junchao@arch6k ~/work/ruapu                                                                                                                                                        [14:58:16] 
> $lscpu                                                                                                                                                                           [±master]
Architecture:          loongarch64
  CPU op-mode(s):      32-bit, 64-bit
  Address sizes:       48 bits physical, 48 bits virtual
  Byte Order:          Little Endian
CPU(s):                8
  On-line CPU(s) list: 0-7
Model name:            Loongson-3A6000
  CPU family:          Loongson-64bit
  Model:               0x00
  Thread(s) per core:  1
  Core(s) per socket:  8
  Socket(s):           1
  BogoMIPS:            5000.00
  Flags:               cpucfg lam ual fpu lsx lasx crc32 complex crypto lvz lbt_x86 lbt_arm lbt_mips
Caches (sum of all):   
  L1d:                 512 KiB (8 instances)
  L1i:                 512 KiB (8 instances)
  L2:                  2 MiB (8 instances)
  L3:                  16 MiB (1 instance)
NUMA:                  
  NUMA node(s):        1
  NUMA node0 CPU(s):   0-7

junchao@arch6k ~/work/ruapu                                                                                                                                                        [14:52:36] 
> $ gcc main.c -o ruapu                                                                                                                                                            [±master]
                                                                                                                                                                                              
junchao@arch6k ~/work/ruapu                                                                                                                                                        [14:52:39] 
> $./ruapu                                                                                                                                                                         [±master]
lsx = 1
lasx = 1

[nihui]

incredible work !

[nihui]

cpucfg lam ual fpu lsx lasx crc32 complex crypto lvz lbt_x86 lbt_arm lbt_mips
剩下的这些能搞吗

[junchao-loongson]

我整理下，下周把能加的加上