Remove "screenshot"

Remove the old "screenshot" utility, which has been replaced
by "screencap".

Change-Id: I5bad1fdad308339e4a16ce92f2a65e2437b1be65
diff --git a/target/product/base.mk b/target/product/base.mk
index 657d88c..36f1f97 100644
--- a/target/product/base.mk
+++ b/target/product/base.mk
@@ -97,7 +97,6 @@
     racoon \
     run-as \
     schedtest \
-    screenshot \
     sdcard \
     services \
     settings \