Configure: Silence spurious warnings from Embarcadero compiler.

As described in the issues below, Embarcadero compilers emit a spurious warning
when including windows.h, if compiling with the C (not C++) language.

    http://qc.embarcadero.com/wc/qcmain.aspx?d=104595
    [BCC32 Warning] winnt.h(14966)...

    http://qc.embarcadero.com/wc/qcmain.aspx?d=127681
    Annoying warnings upon inclusion of <windows.h> in .C source file

Change-Id: Ie8014edea7e8bbdd76f4555ec2d6cd6d90490032

Configure.h.in

@@ -115,6 +115,11 @@
 #  pragma warning (disable: 4710) /* function not inlined */
 #  pragma warning (disable: 4786) /* identifier truncated in debug info */
 # endif
+# if defined(__BORLANDC__) && !defined(__cplusplus)
+   /* Code has no effect; raised by winnt.h in C (not C++) when ignoring an
+      unused parameter using "(param)" syntax (i.e. no cast to void).  */
+#  pragma warn -8019
+# endif
 #endif
 
 /* MSVC 6.0 in release mode will warn about code it produces with its

SharedForward.h.in

@@ -74,6 +74,12 @@
 # endif
 #endif
 
+#if defined(__BORLANDC__) && !defined(__cplusplus)
+  /* Code has no effect; raised by winnt.h in C (not C++) when ignoring an
+     unused parameter using "(param)" syntax (i.e. no cast to void).  */
+# pragma warn -8019
+#endif
+
 /*--------------------------------------------------------------------------*/
 
 /* Full path to the directory in which this executable is built.  Do