Update references to sdkext

The module is getting renamed to sdkextensions.

Bug: 137191822
Test: presubmit
Change-Id: I628fc555b82e9bd931c8f0cce2222b02efad6036
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index 7c7d7b8..f49aee9 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -330,7 +330,7 @@
     telephony-common \
     voip-common \
     ims-common \
-    framework-sdkext \
+    framework-sdkextensions \
     framework-statsd \
     ike \
     updatable-media \
@@ -346,7 +346,7 @@
     com.android.media:updatable-media \
     com.android.mediaprovider:framework-mediaprovider \
     com.android.os.statsd:framework-statsd \
-    com.android.sdkext:framework-sdkext \
+    com.android.sdkext:framework-sdkextensions \
     com.android.wifi:framework-wifi \
     com.android.tethering:framework-tethering