[mono] Add cmake check for HAVE_CLOCK_GETTIME (#88428)

Fixes an issue with missing method names when perf is used together with BenchmarkDotNet using Mono on Linux due to incorrect event order of the fork events and the mmap2 events.

src/mono/cmake/config.h.in

@@ -957,6 +957,9 @@
 /* Enable WebCIL image loader */
 #cmakedefine ENABLE_WEBCIL 1
 
+/* define if clockgettime exists */
+#cmakedefine HAVE_CLOCK_GETTIME 1
+
 #if defined(ENABLE_LLVM) && defined(HOST_WIN32) && defined(TARGET_WIN32) && (!defined(TARGET_AMD64) || !defined(_MSC_VER))
 #error LLVM for host=Windows and target=Windows is only supported on x64 MSVC build.
 #endif

src/mono/cmake/configure.cmake

@@ -115,6 +115,8 @@ ac_check_funcs(
   pthread_attr_setstacksize pthread_get_stackaddr_np
 )
 
+check_function_exists(clock_gettime HAVE_CLOCK_GETTIME)
+
 check_symbol_exists(madvise "sys/mman.h" HAVE_MADVISE)
 check_symbol_exists(pthread_mutexattr_setprotocol "pthread.h" HAVE_DECL_PTHREAD_MUTEXATTR_SETPROTOCOL)
 check_symbol_exists(CLOCK_MONOTONIC "time.h" HAVE_CLOCK_MONOTONIC)