Fail gracefully if memory allocation did not succeed

Testing: precheckin (http://ocltc.amd.com:8111/viewModification.html?modId=69427&personal=true&tab=vcsModificationBuilds)

[git-p4: depot-paths = "//depot/stg/hsa/drivers/hsa/runtime/": change = 1256179]

runtime/hsa-runtime/core/runtime/amd_loader_context.cpp

@@ -472,7 +472,10 @@ void* LoaderContext::SegmentAlloc(amdgpu_hsa_elf_segment_t segment,
   if (nullptr == mem) {
     return nullptr;
   }
-  mem->Allocate(size, align, zero);
+  if (!mem->Allocate(size, align, zero)) {
+    delete mem;
+    return nullptr;
+  }
   return mem;
 }