fix typo in visibility.texi

[Jim Meyering]

FYI:

        * visibility.texi: Remove duplicate word: "pointer".

Index: visibility.texi
===================================================================
RCS file: /sources/gnulib/gnulib/doc/visibility.texi,v
retrieving revision 1.2
diff -u -r1.2 visibility.texi
--- visibility.texi     14 Aug 2006 22:19:55 -0000      1.2
+++ visibility.texi     27 Aug 2006 20:38:41 -0000
@@ -42,7 +42,7 @@
 can assume that it is in the same shared library is just a direct "call"
 instructions. Similarly for variables: A reference to a global variable
 fetches a pointer in the so-called GOT (global offset table); this pointer
-pointer to the variable's memory. So the code to access it is two memory
+to the variable's memory. So the code to access it is two memory
 load instructions. Whereas for a variable which is known to reside in the
 same shared library, it is just a direct memory access: one memory load
 instruction.