Use a different linker for ASan binaries.

Another change in bionic/linker adds linker_asan/linker_asan64 that
know where to find ASan shared libraries.
Also, include linker_asan to the required packages list when building
for ASan.

Change-Id: I8ebe7c0091bbeb0c135708a891d33d9844373d37
diff --git a/core/definitions.mk b/core/definitions.mk
index 442501e..1988cc1 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1510,7 +1510,7 @@
 define transform-o-to-executable-inner
 $(hide) $(PRIVATE_CXX) -pie \
 	-nostdlib -Bdynamic \
-	-Wl,-dynamic-linker,$($(PRIVATE_2ND_ARCH_VAR_PREFIX)TARGET_LINKER) \
+	-Wl,-dynamic-linker,$(PRIVATE_LINKER) \
 	-Wl,--gc-sections \
 	-Wl,-z,nocopyreloc \
 	$(PRIVATE_TARGET_GLOBAL_LD_DIRS) \