Revert "Disable dexpreopt for aosp_riscv64"

This reverts commit ae7f543b7c.

Reason for revert: Enabling dexpreopt for RISC-V (there is still no
  compiler support, but dex2oat runs in verification mode and does
  not attempt any compilation with https://r.android.com/2510739).

Change-Id: I0a6d0416bec51131f0a54c7ff5b0e194728452b1

core/board_config.mk

@@ -204,10 +204,7 @@ _board_strip_readonly_list += $(_build_broken_var_list) \
 
 # Conditional to building on linux, as dex2oat currently does not work on darwin.
 ifeq ($(HOST_OS),linux)
-  # TODO(riscv64) add compiler support and enable dexpreopt on RISC-V.
-  ifneq ($(TARGET_ARCH),riscv64)
-    WITH_DEXPREOPT := true
-  endif
+  WITH_DEXPREOPT := true
 endif
 
 # ###############################################################

core/dex_preopt_config.mk

@@ -65,12 +65,9 @@ ifeq ($(HOST_OS),linux)
   # Non eng linux builds must have preopt enabled so that system server doesn't run as interpreter
   # only. b/74209329
   ifeq (,$(filter eng, $(TARGET_BUILD_VARIANT)))
-    # TODO(riscv64) add compiler support and enable dexpreopt on RISC-V.
-    ifeq (,$(filter riscv64, $(TARGET_ARCH)))
-      ifneq (true,$(WITH_DEXPREOPT))
-        ifneq (true,$(WITH_DEXPREOPT_BOOT_IMG_AND_SYSTEM_SERVER_ONLY))
-          $(call pretty-error, DEXPREOPT must be enabled for user and userdebug builds)
-        endif
+    ifneq (true,$(WITH_DEXPREOPT))
+      ifneq (true,$(WITH_DEXPREOPT_BOOT_IMG_AND_SYSTEM_SERVER_ONLY))
+        $(call pretty-error, DEXPREOPT must be enabled for user and userdebug builds)
       endif
     endif
   endif

target/board/generic_riscv64/BoardConfig.mk

@@ -26,6 +26,3 @@ include build/make/target/board/BoardConfigGsiCommon.mk
 
 # Temporary hack while prebuilt modules are missing riscv64.
 ALLOW_MISSING_DEPENDENCIES := true
-
-# Temporary until dex2oat works when targeting riscv64
-WITH_DEXPREOPT := false