regex_old.c: remove unneeded guard

_LIBC is undefined here, no need to specially guard with __UCLIBC__

Signed-off-by: Peter S. Mazinger <ps.m@gmx.net>
Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>

libc/misc/regex/regex_old.c

@@ -64,10 +64,9 @@
 #  include <wctype.h>
 # endif
 
-# if defined _LIBC || defined __UCLIBC__
+# ifdef _LIBC
 /* We have to keep the namespace clean.  */
 
-# ifndef __UCLIBC__
 #  define btowc __btowc
 
 /* We are also using some library internals.  */
@@ -76,7 +75,6 @@
 #  include <langinfo.h>
 #  include <locale/coll-lookup.h>
 # endif
-# endif
 
 /* This is for other GNU distributions with internationalized messages.  */
 # if defined HAVE_LIBINTL_H || defined _LIBC