qom: Add memory-backend-epc ObjectOptions support

Add the new 'memory-backend-epc' user creatable QOM object in
the ObjectOptions to support SGX since v6.1, or the sgx backend
object cannot bootup.

Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20210719112136.57018-4-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qapi/qom.json

@@ -647,6 +647,23 @@
             '*hugetlbsize': 'size',
             '*seal': 'bool' } }
 
+##
+# @MemoryBackendEpcProperties:
+#
+# Properties for memory-backend-epc objects.
+#
+# The @share boolean option is true by default with epc
+#
+# The @merge boolean option is false by default with epc
+#
+# The @dump boolean option is false by default with epc
+#
+# Since: 6.2
+##
+{ 'struct': 'MemoryBackendEpcProperties',
+  'base': 'MemoryBackendProperties',
+  'data': {} }
+
 ##
 # @PrManagerHelperProperties:
 #
@@ -797,6 +814,7 @@
     { 'name': 'memory-backend-memfd',
       'if': 'CONFIG_LINUX' },
     'memory-backend-ram',
+    'memory-backend-epc',
     'pef-guest',
     'pr-manager-helper',
     'qtest',
@@ -855,6 +873,7 @@
       'memory-backend-memfd':       { 'type': 'MemoryBackendMemfdProperties',
                                       'if': 'CONFIG_LINUX' },
       'memory-backend-ram':         'MemoryBackendProperties',
+      'memory-backend-epc':         'MemoryBackendEpcProperties',
       'pr-manager-helper':          'PrManagerHelperProperties',
       'qtest':                      'QtestProperties',
       'rng-builtin':                'RngProperties',