[vm] Fix error building with musl.

TEST=local build
Change-Id: I50cfd5f84a5c41da2e54dfa7bdd465f91380433c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/294623
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
diff --git a/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc b/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc
index 16185ac..d0bc0ff 100644
--- a/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc
+++ b/runtime/bin/ffi_test/ffi_test_functions_vmspecific.cc
@@ -217,7 +217,7 @@
   fprintf(stderr, "**** EXPECT STACKTRACE TO FOLLOW. THIS IS OK. ****\n");
 
   struct sigaction old_action = {};
-  intptr_t result = __sigsetjmp(buf, /*savesigs=*/1);
+  intptr_t result = sigsetjmp(buf, /*savesigs=*/1);
   if (result == 0) {
     // Install signal handler.
     struct sigaction handler = {};