isaspec: Add method to get the displayname of BitSetEnumValue

This is needed for an assembler use case.

Signed-off-by: Christian Gmeiner <cgmeiner@igalia.com>
Acked-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28920>

src/compiler/isaspec/isa.py

@@ -420,6 +420,9 @@ class BitSetEnumValue(object):
     def get_name(self):
         return self.name or self.displayname
 
+    def get_displayname(self):
+        return self.displayname or self.name
+
     def get_value(self):
         return self.value