tests: add extra_vpp_heap_config knob for main-heap-size

Adds overridable class variable to control VPP's memory { main-heap-size }
config.

Type: improvement
Change-Id: I581d296f3dbde2d4ed2ffac15b7713d580f7cd12
Signed-off-by: Klement Sekera <ksekera@netgate.com>

Author: Klement Sekera

test/asf/asfframework.py

@@ -324,6 +324,7 @@ class VppAsfTestCase(CPUInterface, unittest.TestCase):
     extra_vpp_statseg_config = ""
     extra_vpp_config = []
     extra_vpp_plugin_config = []
+    extra_vpp_heap_config = None
     logger = null_logger
     vapi_response_timeout = 5
     remove_configured_vpp_objects_on_tear_down = True
@@ -457,6 +458,20 @@ def setUpConstants(cls):
         cls.vpp_cmdline.extend(
             [
                 "}",
+            ]
+        )
+        if cls.extra_vpp_heap_config:
+            cls.vpp_cmdline.extend(
+                [
+                    "memory",
+                    "{",
+                    "main-heap-size",
+                    cls.extra_vpp_heap_config,
+                    "}",
+                ]
+            )
+        cls.vpp_cmdline.extend(
+            [
                 "physmem",
                 "{",
                 "max-size",