Fix -Wshorten-64-to-32 errors in Haystack

(This is a merge of http://go/wvgerrit/134424.)

This patch fixes code that would trigger -Wshorten-64-to-32 by
implicitly narrowing a variable from 64 to 32 bits. The membarrier
functions have their return type expanded so they can report the full
return value of the syscall.

Bug: 194971260
Test: x86-64
Change-Id: I5d948162b1f3f1540288df9494cabda39ecf8905

libwvdrmengine/level3/include/clear_cache_function.h

@@ -42,7 +42,7 @@ bool supports_membarier_syscall() {
 // Reference:
 // * membarrier(2)
 // * art::jit::JitMemoryRegion::CommitCode
-int membarrier_function(int command) {
+long membarrier_function(int command) {
   static bool supports_membarier = supports_membarier_syscall();
   if (supports_membarier) {
     return syscall(__NR_membarrier, command, 0);
@@ -55,7 +55,7 @@ int membarrier_function(int command) {
 #  pragma message \
       "(info): __NR_membarrier unavailable; membarrier_function will be no-op."
 
-int membarrier_function(int) {
+long membarrier_function(int) {
   errno = ENOSYS;
   return -1;
 }