Tests+Userland: Implement AARCH64 support for some inline assembly blobs

Author: https://github.com/gunnarbeutner
Commit: 808c43312d
Pull-request: https://github.com/SerenityOS/serenity/pull/15558
Reviewed-by: https://github.com/BertalanD
Reviewed-by: https://github.com/FireFox317
Reviewed-by: https://github.com/awesomekling ✅
Reviewed-by: https://github.com/linusg

Userland/Libraries/LibC/crt0.cpp

@@ -25,9 +25,14 @@ void _start(int, char**, char**) __attribute__((used));
 
 NAKED void _start(int, char**, char**)
 {
+#    ifdef AK_ARCH_AARCH64
+    asm(
+        "bl _entry\n");
+#    else
     asm(
         "push $0\n"
         "jmp _entry@plt\n");
+#    endif
 }
 
 int _entry(int argc, char** argv, char** env)