[libomptarget][amdgpu] Add hidden_heap_v1 kernarg metadata

[saiislam]

Summary

Code object version 5 adds support of hidden_heap_v1 kernarg
metadata field [1]. It is a global address space pointer to an
initialized memory buffer that conforms to the requirements of the
malloc/free device library V1 version implementation.

[1] https://llvm.org/docs/AMDGPUUsage.html#amdgpu-amdhsa-code-object-kernel-argument-metadata-map-table-v5

[carlo.bertolli]

LGTM, thanks for this.

openmp/libomptarget/plugins/amdgpu/impl/system.cpp

enum class ValueKind {
     HiddenGlobalOffsetY,
     HiddenGlobalOffsetZ,
     HiddenNone,
     HiddenPrintfBuffer,
     HiddenDefaultQueue,
     HiddenCompletionAction,
     HiddenMultiGridSyncArg,
     HiddenHostcallBuffer,
+    HiddenHeapV1,
     Unknown
   };
 
   KernelArgMD()
       : name_(std::string()),  size_(0), offset_(0),
         valueKind_(ValueKind::Unknown) {}
 
   // fields
static const std::map<std::string, KernelArgMD::ValueKind> ArgValueKind = {
     {"hidden_none", KernelArgMD::ValueKind::HiddenNone},
     {"hidden_printf_buffer", KernelArgMD::ValueKind::HiddenPrintfBuffer},
     {"hidden_default_queue", KernelArgMD::ValueKind::HiddenDefaultQueue},
     {"hidden_completion_action",
      KernelArgMD::ValueKind::HiddenCompletionAction},
     {"hidden_multigrid_sync_arg",
      KernelArgMD::ValueKind::HiddenMultiGridSyncArg},
     {"hidden_hostcall_buffer", KernelArgMD::ValueKind::HiddenHostcallBuffer},
+    {"hidden_heap_v1", KernelArgMD::ValueKind::HiddenHeapV1}
 };
 
 namespace core {
 
 hsa_status_t callbackEvent(const hsa_amd_event_t *event, void *data) {
   if (event->event_type == HSA_AMD_GPU_MEMORY_FAULT_EVENT) {
     hsa_amd_gpu_memory_fault_info_t memory_fault = event->memory_fault;
     // memory_fault.agent
static bool isImplicit(KernelArgMD::ValueKind value_kind) {
   case KernelArgMD::ValueKind::HiddenGlobalOffsetY:
   case KernelArgMD::ValueKind::HiddenGlobalOffsetZ:
   case KernelArgMD::ValueKind::HiddenNone:
   case KernelArgMD::ValueKind::HiddenPrintfBuffer:
   case KernelArgMD::ValueKind::HiddenDefaultQueue:
   case KernelArgMD::ValueKind::HiddenCompletionAction:
   case KernelArgMD::ValueKind::HiddenMultiGridSyncArg:
   case KernelArgMD::ValueKind::HiddenHostcallBuffer:
+  case KernelArgMD::ValueKind::HiddenHeapV1:
     return true;
   default:
     return false;
   }
 }
 
 static std::pair<unsigned char *, unsigned char *>
 find_metadata(void *binary, size_t binSize) {