perf arm64: Use max_nr to define SYSCALLTBL_ARM64_MAX_ID

Like x86, powerpc, mips and s390, use max_nr which is a digital
number to define SYSCALLTBL_ARM64_MAX_ID.

Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: loongarch@lists.linux.dev
Link: https://lore.kernel.org/r/1685441401-8709-5-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/arm64/entry/syscalls/mksyscalltbl

@@ -21,14 +21,14 @@ fi
 
 create_sc_table()
 {
-	local sc nr last_sc
+	local sc nr max_nr
 
 	while read sc nr; do
 		printf "%s\n" "	[$nr] = \"$sc\","
-		last_sc=$sc
+		max_nr=$nr
 	done
 
-	printf "%s\n" "#define SYSCALLTBL_ARM64_MAX_ID __NR_$last_sc"
+	echo "#define SYSCALLTBL_ARM64_MAX_ID $max_nr"
 }
 
 create_table()