Revert "Update naming of platforms subdir"

This reverts commit 8b22209184.

Reason for revert: Doesn't match install path for pre-release SDKs

Change-Id: Ic1ce28e57692d27d08d33dee5b7403bf1bf1b655

core/Makefile

@@ -6824,11 +6824,7 @@ $(INTERNAL_SDK_TARGET): PRIVATE_NAME := $(sdk_name)
 $(INTERNAL_SDK_TARGET): PRIVATE_DIR := $(sdk_dir)/$(sdk_name)
 $(INTERNAL_SDK_TARGET): PRIVATE_DEP_FILE := $(sdk_dep_file)
 $(INTERNAL_SDK_TARGET): PRIVATE_INPUT_FILES := $(sdk_atree_files)
-$(INTERNAL_SDK_TARGET): PRIVATE_PLATFORM_NAME := \
-  $(strip $(if $(filter $(PLATFORM_SDK_EXTENSION_VERSION),$(PLATFORM_BASE_SDK_EXTENSION_VERSION)),\
-    android-$(PLATFORM_SDK_VERSION),\
-    android-$(PLATFORM_SDK_VERSION)-ext$(PLATFORM_SDK_EXTENSION_VERSION)) \
-)
+
 # Set SDK_GNU_ERROR to non-empty to fail when a GNU target is built.
 #
 #SDK_GNU_ERROR := true
@@ -6853,7 +6849,7 @@ $(INTERNAL_SDK_TARGET): $(deps)
 	        -I $(PRODUCT_OUT) \
 	        -I $(HOST_OUT) \
 	        -I $(TARGET_COMMON_OUT_ROOT) \
-	        -v "PLATFORM_NAME=$(PRIVATE_PLATFORM_NAME)" \
+	        -v "PLATFORM_NAME=android-$(PLATFORM_VERSION)" \
 	        -v "OUT_DIR=$(OUT_DIR)" \
 	        -v "HOST_OUT=$(HOST_OUT)" \
 	        -v "TARGET_ARCH=$(TARGET_ARCH)" \