Set crosshatch cpu "runtime variant" to kryo385

This makes bionic and various art tools that compile/runs cpu-specific
code choose the kryo385 variant at runtime. It does not affect
build-time compilation.

Bug: 120773446
Test: bionic benchmarks with and without this change
Change-Id: I670c8acd094090135515688c5f057c2cc08a083f

BoardConfig-common.mk

diff --git a/BoardConfig-common.mk b/BoardConfig-common.mk
index 6da22e8..d255a25 100644
--- a/BoardConfig-common.mk
+++ b/BoardConfig-common.mk
@@ -24,12 +24,14 @@
 TARGET_CPU_ABI := arm64-v8a
 TARGET_CPU_ABI2 :=
 TARGET_CPU_VARIANT := generic
+TARGET_CPU_VARIANT_RUNTIME := kryo385
 
 TARGET_2ND_ARCH := arm
 TARGET_2ND_ARCH_VARIANT := armv8-a
 TARGET_2ND_CPU_ABI := armeabi-v7a
 TARGET_2ND_CPU_ABI2 := armeabi
 TARGET_2ND_CPU_VARIANT := generic
+TARGET_2ND_CPU_VARIANT_RUNTIME := kryo385
 
 TARGET_BOARD_COMMON_PATH := device/google/crosshatch/sdm845