arm: Fix clang multi-arch build with ld.bfd

clang binds autogenerated memcpy/memset/memchr calls to the hidden
internal symbols, different than gcc that binds without hidden
attribute.  And this triggers an linker issue with bfd:

  ld: BFD (GNU Binutils for Ubuntu) 2.38 assertion fail
  ../../bfd/elf32-arm.c:4286

Similar to other architectures, bind internal memcpy and memcpy
symbols to the generic interface instead.

sysdeps/arm/arm-ifunc.h

@@ -23,12 +23,3 @@
 
 #define arm_libc_ifunc_redirected(redirected_name, name, expr)	\
   __ifunc (redirected_name, name, expr(hwcap), int hwcap, INIT_ARCH)
-
-#if defined SHARED
-# define arm_libc_ifunc_hidden_def(redirect_name, name) \
-  __hidden_ver1 (name, __GI_##name, redirect_name) \
-    __attribute__ ((visibility ("hidden"))) \
-    __attribute_copy__ (name)
-#else
-# define arm_libc_ifunc_hidden_def(redirect_name, name)
-#endif

sysdeps/arm/armv7/multiarch/memchr.c

@@ -30,6 +30,4 @@
 # include "ifunc-memchr.h"
 
 arm_libc_ifunc_redirected (__redirect_memchr, memchr, IFUNC_SELECTOR);
-
-arm_libc_ifunc_hidden_def (__redirect_memchr, memchr);
 #endif

sysdeps/arm/armv7/multiarch/memchr_noneon.S

@@ -3,3 +3,7 @@
 #define libc_hidden_builtin_def(name)
 
 #include <sysdeps/arm/armv6t2/memchr.S>
+
+#if IS_IN (libc) && !defined (__ARM_NEON__)
+strong_alias (__memchr_noneon, __GI_memchr)
+#endif

sysdeps/arm/armv7/multiarch/memcpy.c

@@ -30,6 +30,4 @@
 # include "ifunc-memcpy.h"
 
 arm_libc_ifunc_redirected (__redirect_memcpy, memcpy, IFUNC_SELECTOR);
-
-arm_libc_ifunc_hidden_def (__redirect_memcpy, memcpy);
 #endif

sysdeps/arm/armv7/multiarch/memcpy_arm.S

@@ -8,3 +8,7 @@
 strong_alias (__memcpy_arm, __aeabi_memcpy)
 strong_alias (__memcpy_arm, __aeabi_memcpy4)
 strong_alias (__memcpy_arm, __aeabi_memcpy8)
+
+#if IS_IN (libc) && !defined (__ARM_NEON__)
+strong_alias (__memcpy_arm, __GI_memcpy)
+#endif