Remove RS_SERVER macros and references to unused headers.

 - The RS_SERVER macros were intended to have a version of RenderScript
 running on the desktop.  It has not fully worked for a very long time.

Bug: 35473587
Test: build and CTS tests pass
Change-Id: I0da3fc9d4601951442384d05f9dbecaeddeff8cc
diff --git a/cpp/rsCppStructs.h b/cpp/rsCppStructs.h
index ae7291a..1b533d0 100644
--- a/cpp/rsCppStructs.h
+++ b/cpp/rsCppStructs.h
@@ -651,7 +651,7 @@
      */
     void ioGetInput();
 
-#if !defined(RS_SERVER) && !defined(RS_COMPATIBILITY_LIB)
+#ifndef RS_COMPATIBILITY_LIB
     /**
      * Returns the handle to a raw buffer that is being managed by the screen
      * compositor. This operation is only valid for Allocations with USAGE_IO_INPUT.