remove use of mach_absolute_time
`mach_absolute_time` is one of Apple's required reason APIs (https://developer.apple.com/documentation/kernel/1462446-mach_absolute_time?language=objc). Replace it with the suggested `clock_gettime_nsec_np(CLOCK_UPTIME_RAW)` so that we don't need a RRA entry in a privacy manifest.
issue #15029
diff --git a/src/google/protobuf/map.h b/src/google/protobuf/map.h
index 4ea4224..e28c1c6 100644
--- a/src/google/protobuf/map.h
+++ b/src/google/protobuf/map.h
@@ -25,7 +25,7 @@
#include <utility>
#if !defined(GOOGLE_PROTOBUF_NO_RDTSC) && defined(__APPLE__)
-#include <mach/mach_time.h>
+#include <time.h>
#endif
#include "google/protobuf/stubs/common.h"
@@ -676,7 +676,7 @@
#if defined(__APPLE__)
// Use a commpage-based fast time function on Apple environments (MacOS,
// iOS, tvOS, watchOS, etc).
- s = mach_absolute_time();
+ s = clock_gettime_nsec_np(CLOCK_UPTIME_RAW);
#elif defined(__x86_64__) && defined(__GNUC__)
uint32_t hi, lo;
asm volatile("rdtsc" : "=a"(lo), "=d"(hi));
