elfutils: towards uClibc support: solve memcpy problem

elfutils uses some strange internal alias of memcpy in glibc, so
workaround this when building with uClibc.

Heavily based from work done by Stefan Fröberg, but with many further
modifications by Thomas Petazzoni.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/elfutils/elfutils-03-memcpy-def.patch

@@ -0,0 +1,24 @@
+Provide a compatibility alias __memcpy
+
+For some reason, libelf uses the internal glibc alias __memcpy, which
+doesn't exist in uClibc. Add a manual alias so that the build can
+proceed with uClibc.
+
+Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+
+Index: b/libelf/libelf.h
+===================================================================
+--- a/libelf/libelf.h
++++ b/libelf/libelf.h
+@@ -34,6 +34,11 @@
+ /* Get the ELF types.  */
+ #include <elf.h>
+ 
++#ifndef _LIBC
++#ifndef __mempcpy
++#define __mempcpy mempcpy
++#endif
++#endif
+ 
+ /* Known translation types.  */
+ typedef enum