Remove PRODUCT_MEMCG_V2_FORCE_ENABLED

Commit 18a5d3920a ("Add flags for cgroup v2 and memcg v2 features")
added a build flag that allows forcing the memory cgroup controller to
v2 when PRODUCT_MEMCG_V2_FORCE_ENABLED is true. However the memory
controller is now v2 by default since commit 5fa48a84b
("libprocessgroup: memcg default version 1 -> 2") so this build flag is
no longer needed.

Bug: 327480673
Bug: 377579705
Change-Id: I770efa71d8f57abee58adc2be4bac097d35e3b34
diff --git a/core/android_soong_config_vars.mk b/core/android_soong_config_vars.mk
index 862fcb2..ed3eed1 100644
--- a/core/android_soong_config_vars.mk
+++ b/core/android_soong_config_vars.mk
@@ -122,10 +122,6 @@
 $(call soong_config_set_bool,ANDROID,target_boots_16k,$(filter true,$(TARGET_BOOTS_16K)))
 endif
 
-ifdef PRODUCT_MEMCG_V2_FORCE_ENABLED
-$(call add_soong_config_var_value,ANDROID,memcg_v2_force_enabled,$(PRODUCT_MEMCG_V2_FORCE_ENABLED))
-endif
-
 ifdef PRODUCT_CGROUP_V2_SYS_APP_ISOLATION_ENABLED
 $(call add_soong_config_var_value,ANDROID,cgroup_v2_sys_app_isolation,$(PRODUCT_CGROUP_V2_SYS_APP_ISOLATION_ENABLED))
 else