Fix `arm_v7_v8` device config.

Test: buildbot-build.sh --target
Bug: 336524777
Change-Id: I1777bd2cef5806acaaaee069dae6ec36b8f8249e
diff --git a/arm_v7_v8/BoardConfig.mk b/arm_v7_v8/BoardConfig.mk
index b252033..e30e784 100644
--- a/arm_v7_v8/BoardConfig.mk
+++ b/arm_v7_v8/BoardConfig.mk
@@ -24,7 +24,7 @@
 
 TARGET_2ND_ARCH := arm
 TARGET_2ND_ARCH_VARIANT := armv7-a-neon
-TARGET_2ND_CPU_VARIANT := cortex-a15
+TARGET_2ND_CPU_VARIANT := generic
 TARGET_2ND_CPU_ABI := armeabi-v7a
 TARGET_2ND_CPU_ABI2 := armeabi