Work around portability problems with Visual Age C compiler

(xlc and xlC_r) reported by John P. Hartmann.
* data/location.cc (initial_column, initial_line): Remove.
All uses replaced by 0 and 1.
* src/scan-gram.l (gram_wrap): Redefine to avoid bug in flex 2.5.31
that xlc complains about.
* src/scan-skel.l (skel_wrap): Likewise.

src/scan-gram.l

@@ -24,6 +24,11 @@
 %option prefix="gram_" outfile="lex.yy.c"
 
 %{
+/* Work around a bug in flex 2.5.31.  See Debian bug 333231
+   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
+#undef gram_wrap
+#define gram_wrap() 1
+
 #include "system.h"
 
 #include <mbswidth.h>

src/scan-skel.l

@@ -23,6 +23,11 @@
 %option prefix="skel_" outfile="lex.yy.c"
 
 %{
+/* Work around a bug in flex 2.5.31.  See Debian bug 333231
+   <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
+#undef skel_wrap
+#define skel_wrap() 1
+
 #include "system.h"
 
 #include <error.h>