Add support for 64 bit LoongArch compilation

Add 64 bit LoongArch architecture by defining ACPI_MACHINE_WIDTH to 64.
Useful for acpica tools and incorporating ACPICA into the Firmware Test
Suite.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

source/include/platform/aclinux.h

@@ -329,7 +329,7 @@
 
 #if defined(__ia64__)    || (defined(__x86_64__) && !defined(__ILP32__)) ||\
     defined(__aarch64__) || defined(__PPC64__) ||\
-    defined(__s390x__) ||\
+    defined(__s390x__)   || defined(__loongarch__) ||\
     (defined(__riscv) && (defined(__LP64__) || defined(_LP64)))
 #define ACPI_MACHINE_WIDTH          64
 #define COMPILER_DEPENDENT_INT64    long