dev-hsa,gpu-compute: Fix override for updateHsaSignal

Change 965ad12 removed a parameter from the updateHsaSignal
function. Change 25e8a14 added the parameter back, but only for the
derived class, breaking the override. This patch adds that parameter
back to the base class, fixing the override.

Change-Id: Id1e96e29ca4be7f3ce244bac83a112e3250812d1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/44046
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Alex Dutu <alexandru.dutu@amd.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>

src/dev/hsa/hsa_device.hh

@@ -101,7 +101,8 @@ class HSADevice : public DmaDevice
         fatal("%s does not need HSA driver\n", name());
     }
     virtual void
-    updateHsaSignal(Addr signal_handle, uint64_t signal_value)
+    updateHsaSignal(Addr signal_handle, uint64_t signal_value,
+        HsaSignalCallbackFunction function = [] (const uint64_t &) { })
     {
         fatal("%s does not have HSA signal update functionality.\n", name());
     }

src/gpu-compute/gpu_command_processor.hh

@@ -90,7 +90,7 @@ class GPUCommandProcessor : public HSADevice
 
     void updateHsaSignal(Addr signal_handle, uint64_t signal_value,
                          HsaSignalCallbackFunction function =
-                            [] (const uint64_t &) { });
+                            [] (const uint64_t &) { }) override;
 
     uint64_t functionalReadHsaSignal(Addr signal_handle) override;