LoongArch: BPI: Declare acpi_arch_init with a void prototype

Fix follow error with clang-19:

arch/loongarch/kernel/legacy_boot.c:687:28: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes]
  687 | void __init acpi_arch_init (){
      |                            ^
      |                             void
1 error generated.

Signed-off-by: WangYuli <[email protected]>

arch/loongarch/kernel/legacy_boot.c

@@ -684,7 +684,7 @@ static __initconst const struct {
 	},
 };
 
-void __init acpi_arch_init (){
+void __init acpi_arch_init (void){
 	if (bpi_version == BPI_VERSION_NONE) {
 		return;
 	}