streq fix

[Bruno Haible]

This include file was missing a double-inclusion guard.

2007-09-01  Bruno Haible  <address@hidden>

        * lib/streq.h: Add double-inclusion guard.

*** lib/streq.h 24 Jan 2007 02:45:50 -0000      1.1
--- lib/streq.h 1 Sep 2007 16:24:09 -0000
***************
*** 18,23 ****
--- 18,26 ----
  
  /* Written by Bruno Haible <address@hidden>.  */
  
+ #ifndef _GL_STREQ_H
+ #define _GL_STREQ_H
+ 
  #include <string.h>
  
  /* STREQ allows to optimize string comparison with a small literal string.
***************
*** 171,173 ****
--- 174,178 ----
    (strcmp (s1, s2) == 0)
  
  #endif
+ 
+ #endif /* _GL_STREQ_H */