[GWP-ASan] Fix thread ID.

Summary:
GWP-ASan currently reports <unknown> thread ID, as the crash handler
merge dropped the include. Oops.

Reviewers: morehouse

Reviewed By: morehouse

Subscribers: eugenis, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D75693

GitOrigin-RevId: 85c0b34fc5a5e19dee4b5055eaafbb1c2589c233
diff --git a/platform_specific/common_posix.cpp b/platform_specific/common_posix.cpp
index 38e6ce0..e44e629 100644
--- a/platform_specific/common_posix.cpp
+++ b/platform_specific/common_posix.cpp
@@ -8,6 +8,9 @@
 
 #include "gwp_asan/common.h"
 
+#include <sys/syscall.h>
+#include <unistd.h>
+
 namespace gwp_asan {
 
 uint64_t getThreadID() {
diff --git a/platform_specific/guarded_pool_allocator_posix.cpp b/platform_specific/guarded_pool_allocator_posix.cpp
index bef4ef5..a8767a4 100644
--- a/platform_specific/guarded_pool_allocator_posix.cpp
+++ b/platform_specific/guarded_pool_allocator_posix.cpp
@@ -15,7 +15,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
-#include <sys/syscall.h>
 #include <sys/types.h>
 #include <unistd.h>