Update src/core/sys/linux/perf_event.d

Version specifier was incorrect for 64 bit arm

Co-authored-by: Nathan Sashihara <21227491+n8sh@users.noreply.github.com>

Author: maxhaton

src/core/sys/linux/perf_event.d

@@ -26,7 +26,7 @@ else version (ARM)
 {
         enum __NR_perf_event_open = 364;
 }
-else version (ARM64)
+else version (AArch64)
 {
         enum __NR_perf_event_open = 241;
 }