powerpc: Remove duplicate strchrnul and strncasecmp_l libc.a (BZ 31786)

For powerpc64 the generic version provides a weak definition of
strchrnul, which are already provided by the ifunc resolver.  The
powerpc32 version is slight different, where for static case there
is no iFUNC support.

The strncasecmp_l is provided ifunc resolver.

Checked on powerpc-linux-gnu-power4 and powerpc64-linux-gnu.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

sysdeps/powerpc/powerpc64/multiarch/strchrnul-power7.S

@@ -18,6 +18,9 @@
 
 #define STRCHRNUL __strchrnul_power7
 
+#undef weak_alias
+#define weak_alias(a,b)
+
 #undef libc_hidden_builtin_def
 #define libc_hidden_builtin_def(name)
 

sysdeps/powerpc/powerpc64/multiarch/strchrnul-ppc64.c

@@ -16,4 +16,16 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#include <sysdeps/powerpc/powerpc32/power4/multiarch/strchrnul-ppc32.c>
+#include <string.h>
+
+#if IS_IN (libc)
+# define STRCHRNUL  __strchrnul_ppc
+extern __typeof (strchrnul) __strchrnul_ppc attribute_hidden;
+
+# include <string/strchrnul.c>
+# undef __strchrnul
+weak_alias (__strchrnul_ppc, __strchrnul)
+# ifdef SHARED
+__hidden_ver1 (__strchrnul_ppc, __GI___strchrnul, __strchrnul_ppc);
+# endif
+#endif

sysdeps/powerpc/powerpc64/multiarch/strncase_l-power7.c

@@ -19,6 +19,9 @@
 
 #define __strncasecmp_l __strncasecmp_l_power7
 
+#undef weak_alias
+#define weak_alias(a,b)
+
 #undef libc_hidden_def
 #define libc_hidden_def(name)