[PATCH 3/3] powerpc: Fix powerpc64 strchrnul build with old gcc

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

The compiler might not see that internal definition is an alias
due the libc_ifunc macro, which redefines __strchrnul.  With
gcc 6 it fails with:

In file included from <command-line>:0:0:
./../include/libc-symbols.h:472:33: error: ‘__EI___strchrnul’ aliased to
undefined symbol ‘__GI___strchrnul’
   extern thread __typeof (name) __EI_##name \
                                 ^
./../include/libc-symbols.h:468:3: note: in expansion of macro
‘__hidden_ver2’
   __hidden_ver2 (, local, internal, name)
   ^~~~~~~~~~~~~
./../include/libc-symbols.h:476:29: note: in expansion of macro
‘__hidden_ver1’
 #  define hidden_def(name)  __hidden_ver1(__GI_##name, name, name);
                             ^~~~~~~~~~~~~
./../include/libc-symbols.h:557:32: note: in expansion of macro
‘hidden_def’
 # define libc_hidden_def(name) hidden_def (name)
                                ^~~~~~~~~~
../sysdeps/powerpc/powerpc64/multiarch/strchrnul.c:38:1: note: in
expansion of macro ‘libc_hidden_def’
 libc_hidden_def (__strchrnul)
 ^~~~~~~~~~~~~~~

Use libc_ifunc_hidden as stpcpy.  Checked on powerpc64 with
gcc 6 and gcc 13.
---
 sysdeps/powerpc/powerpc64/multiarch/strchrnul.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c b/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
index 94873507a6..87dd41f72d 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strchrnul.c
@@ -27,13 +27,13 @@ extern __typeof (__strchrnul) __strchrnul_power8 attribute_hidden;
 
 /* Avoid DWARF definition DIE on ifunc symbol so that GDB can handle
    ifunc symbol properly.  */
-libc_ifunc (__strchrnul,
-	    (hwcap2 & PPC_FEATURE2_ARCH_2_07
-	     && hwcap & PPC_FEATURE_HAS_ALTIVEC)
-	    ? __strchrnul_power8 :
-	    (hwcap & PPC_FEATURE_ARCH_2_06)
-            ? __strchrnul_power7
-            : __strchrnul_ppc);
+libc_ifunc_hidden (__strchrnul, __strchrnul,
+		   (hwcap2 & PPC_FEATURE2_ARCH_2_07
+		    && hwcap & PPC_FEATURE_HAS_ALTIVEC)
+		   ? __strchrnul_power8 :
+		   (hwcap & PPC_FEATURE_ARCH_2_06)
+		   ? __strchrnul_power7
+		   : __strchrnul_ppc);
 
 libc_hidden_def (__strchrnul)
 weak_alias (__strchrnul, strchrnul)
-- 
2.34.1